Animal Production Science
Volume 57 Number 6 2017
AN16023Smallholder large ruminant health and production in Lao PDR: challenges and opportunities for improving domestic and regional beef supply
Indigenous yellow cattle (Bos indicus) and Asiatic swamp buffalo (Bubalus bubalis) are important livestock species in Laos. Data from 2011 showed that the majority of farm households with large ruminants were smallholders, with the average numbers of farm household with cattle and buffalo of 5.3 and 3.4, respectively. This paper identifies the strategic interventions that may increase the supply of cattle and buffalo and improve rural livelihoods in Laos and the Greater Mekong Subregion.
AN15376Expression of selected genes related to energy mobilisation and insulin resistance in dairy cows
Age effect on gene expression in peripartum dairy cows was investigated. Age effect on peroxisome proliferator-activated receptor gamma and adiponectin was found in adipose tissue, on SLC2A4 in muscle. The age influence on expression of selected genes involved in energy mobilisation and insulin resistance highlights the importance of a genomics approach to assess the metabolic status of dairy cows during the transition period.
The following manuscript presents the estimation of the effect of polymorphism within µ-calpain gene (CAPN1) on the most important slaughter and fattening traits and characteristics of pork quality. The results obtained will be helpful in verification of potential use of CAPN1 gene as a genetic marker in selection. The presented data would be a base for further research in the field of the genetics of quantitative traits in pigs.
AN15347Random regression model with heterogeneous residual variance reduces polynomial order fitted for permanent environmental effect but does not affect genetic parameters for milk production in Sahiwal cattle
The random regression test-day models can be used for accurate and economical genetic evaluation of Sahiwal cattle. The heritability estimates of monthly test-day milk yields were low to moderate in different lactations and the assumption of homogeneous or heterogeneous residual variance gave similar estimates. Random regression model with homogenous or heterogeneous variance can be used for modelling test-day milk yield and breeding value prediction in Sahiwal cattle.
AN15003Effects of high ambient temperature on meat quality, serum hormone concentrations, and gene expression in the longissimus dorsi muscle of finishing pigs
Few studies have focused on the influence of chronic exposure to high ambient temperature on meat quality of finishing pigs until now. We researched it and found that high temperature decreased intramuscular fat content of pigs because of the reduction in feed intake. Independently of its effect on feed intake, high ambient temperature affected the meat quality of finishing pigs by increasing the pH value and inducing a transition of muscle fibre types from IIb to IIx.
AN15871Pre- and peri-pubertal feed intake: effects on age at puberty and potential litter size of replacement gilts
Productivity of the sow breeding herd is determined by age at puberty and first litter size. From our study, we know that puberty is delayed by long, but not short, periods of mild feed restriction, and that flush feeding increases ovulation rate but not potential litter size. Our study demonstrates the importance of ensuring adequate nutrition throughout the gilt’s life, and indicates that oocyte quality and uterine capacity, rather than ovulation rate, determine first litter size.
AN15241Effect of parity on changes in udder traits, milk yield and composition of West African dwarf sheep during lactation
The West African Dwarf (WAD) sheep have potentials to supply a significant portion of dietary milk for human consumption and some consumers in Nigeria perceived its milk to have a better taste and more natural than cow milk. In spite of this, information about detailed nutritional qualities of this milk is unavailable. This study provides information on the nutritional qualities inherent in consumption of milk produced by WAD sheep, changes on udder traits and concomitant variation in milk yield and composition.
AN15740Interactive effects of dietary protein concentration, a mono-component exogenous protease and ascorbic acid on broiler performance, nutritional status and gut health
Ascorbic acid (vitamin C) is centrally important to the health and welfare of humans and animals and an inadequate supply leads to serious pathologies involving collagen (a key structural protein) integrity. The work presented herein assessed the effect of supplemental ascorbic acid, in association with an exogenous protease, for broiler chickens and it was discovered that adding protease and ascorbic acid to the diet resulted in significant advantages in nutrition, growth and intestinal health. It can be concluded that modern broiler chickens may have a previously unrecognised need for supplemental ascorbic acid and that the benefits from this supplementation may be significantly enhanced by coupling this with exogenous protease to enhance the integrity of the gut and nutrient recovery from feed.
Early lactation dairy cows are frequently in negative energy balance, making them susceptible to serious life-threatening diseases such as ketosis. Because the B-vitamin niacin reduces mobilisation (use) of stored body fat, it may moderate this negative energy balance and reduce blood accumulation of the non-esterified fatty acids that cause ketosis. Low level niacin feeding improved health and production in early lactation cows, but because higher feeding levels had negative impacts, this strategy has limited practical applicability.
AN15860Vitamin A deficiency in Bos indicus heifers fed a wheat straw diet cannot be corrected with algae lick blocks or intramuscular injectable retinyl palmitate treatments
Primary vitamin A deficiency occurs during the dry season in northern Australia when cattle graze senesced forage. Injectable vitamin A or an oral β-carotene source from algae failed to replete vitamin A concentrations in cattle fed a poor quality forage diet. Vitamin A-deficient cattle require concurrent protein and vitamin A supplementation to replete vitamin A concentrations when fed poor quality forage.
AN15641Effects of protected omega-3 fatty acid derived from linseed oil and vitamin E on growth performance, apparent digestibility, blood characteristics and meat quality of finishing pigs
Due to the increased awareness of health benefits derived from omega-3 fatty acid and consumer demand for value-added pork products, this study focused on dietary inclusion of omega-3 and vitamin E singly or in combination to evaluate growth performance, meat quality and blood profile in finishing pigs. The supplementation of vitamin E alone improved surface longissimus muscle redness and increased IgG concentration in serum, whereas the combination of omega-3 fatty acid and vitamin E reduced cortisol concentration in serum. The changes reported here for IgG and cortisol suggest vitamin E and omega-3 have the potential to improve the immune status of growing pigs.
AN15156Low-level arginine supplementation (0.1%) of wheat-based diets in pregnancy increases the total and live-born litter sizes in gilts
Arginine nutrition in gestating sows is essential for porcine embryonic and fetal development. However, arginine supplementation in common corn-soybean basal diet is rather expensive. This study investigated low level L-arginine supplementation in wheat-based diets on the pregnancy outcome of gilts. We found that low-level supplementation (0.1%) of L-arginine–HCl of wheat-based diets beneficially enhances the reproductive performance of gilts and is feasible for use in commercial production.
AN16068Production responses of reproducing ewes to a by-product-based diet inoculated with the probiotic Bacillus amyloliquefaciens strain H57
This paper highlights the potential of a novel probiotic to improve the feeding value of an otherwise low quality pelleted diet for ruminants. By inoculating pellets with the spores of Bacillus amyloliquefaciens strain H57 we noted encouraging improvements in feed intake and maternal liveweight of pregnant ewes. These improvements appeared to persist into lactation and deserve further investigation in commercial ruminant production systems, particularly the application of a diet based on low quality by-products.
AN15819Relationship between time spent eating and nutritionally related blood metabolites of growing pigs fed on diets containing graded levels of fibre
Determining feeding patterns is the first step in understanding acceptability of maize cob-based diets by pigs. The objective of this study was to determine relationships between time spent eating and nutritionally related metabolites in growing pigs. The metabolites were related to the time spent feeding and drinking in pigs. When formulating diets using fibrous ingredients, feed compounders should not only consider only bulk, but also feeding patterns.
AN15830Survival of lambs from maiden ewes may not be improved by pre-lambing exposure to mature lambing ewes
Peri-natal lamb survival is a key limitation to sheep production, which may be improved through modifying ewe behaviour. This study showed that pre-lambing exposure of maiden (first-lambing) ewes to mature lambing ewes using the method reported did not increase and may reduce the survival of their lambs. It is recommended that maiden ewes lamb in separate paddocks to mature ewes until more is known regarding the presence of adult ewes may influence lamb survival from maiden ewes.
AN16030Guardian dogs protect sheep by guarding sheep, not by establishing territories and excluding predators
Guardian dogs have protected livestock from predators for centuries, but how do they work? Repeated occurrences of dingoes/wild dogs inside sheep paddocks patrolled by maremma guardian dogs suggest they guard sheep by preventing interactions not by defending a territory and excluding intruders. Understanding that wild dogs regularly frequent sheep paddocks for hours and sometimes days can be important when considering livestock management practices.
AN15249Effects of different monochromatic LED light colours on fear reactions and physiological responses in Mulard ducks
The colour of the light during rearing periods of birds affects their behaviour, performance and welfare. We investigated the effects of light colours on fear reactions and physiology of Mulard ducks. Rearing ducks in blue or green light reduces their fear reactions and physiological responses to stress and improves their welfare compared with rearing them in red or white colour light.
AN15809Production and health performance of Holstein, Brown Swiss and their crosses under subtropical environmental conditions
From an economic opinion, high culling rates in pure Holstein cows are of great concern to dairy producers. In order to reduce these problems, dairy producers around the world have started to mate pure Holstein cows to bulls from other breeds. The current study indicates that the first generation crossbred (Brown Swiss × Holstein) has a more stable production performance and adaptability than pure Holstein under subtropical conditions.
AN15828Study on the effects of electrical stunning parameters for broilers on biochemical and histological markers of stress and meat quality
Assessment of animal welfare suffering at poultry abattoirs is important because, poor welfare can cause stress and also influence the quality of the meat. Proper electrical stunning conditions can minimise suffering associated with slaughtering, and improve the metabolic changes in muscles responsible for quality meat. To evaluate poultry pre-slaughter stress at the slaughterhouse, clinical signs, electrocardiogram, and electroencephalogram seems not to be feasible and sufficiently rapid parameters. Physicochemical parameters, such as pH and peroxides, might be used as feasible markers of acute pre-slaughter stress and poultry quality meat. Study on Ross broilers (n = 96) indicated that high stunning frequency may improve the quality of poultry meat without aggregating stress.
AN15454Resource use and greenhouse gas emissions from grain-finishing beef cattle in seven Australian feedlots: a life cycle assessment
Agricultural industries face the challenge of maintaining and expanding production to meet global food requirements with fewer resources, while producing lower greenhouse gas (GHG) emissions. This study quantified energy and water use, land occupation and GHG emissions from beef grain-finishing systems in eastern Australia. Fresh water consumption and stress-weighted water use varied in response to regional water availability for feed production. Energy demand, land use and GHG emissions varied in response to average daily gain, which differed between market types.
AN15900Performance of cattle reared on rangelands supplemented with farm-formulated diets during the dry season in Zimbabwe
Annual calving and fast growth rate in cattle is very vital to cattlemen; however, the challenge remains how to achieve that without incurring an extra cost in supplementary feeding. This study evaluated the use of alternate cheap farm produce feed supplements and the results proved to be the winning formula for all resources constrained livestock farmers. With these farm formulated diets cattle grow faster, calve annually and the returns are higher, meaning resources constrained farmers no longer have problems in maximising livestock production to better their lives and improve the food security of many nations.
AN15149Fatty acid profile, carcass traits and meat quality of Nellore steers following supplementation with various lipid sources
The public policies in health suggest population-wide higher intakes of polyunsaturated fatty acids, and lower intakes of saturated fat. Therefore, scientific studies are crucial in providing knowledge to consumers to allow them to assess the pros and cons of eating beef, which in turn has tremendous importance for the global economy. Thus, this experiment demonstrates that the inclusion of linseed oil is recommended as a method for improving the acid linoleic conjugated in the meat of beef cattle.
AN14975Identification of relationship between pork colour and physicochemical traits in American Berkshire by canonical correlation analyses
Consumers are a tendency to the judgment of the meat quality depending on colour. Therefore, it is very important to elucidate the relationships between sets of meat colours and physicochemical characteristic variables. In order to produce a reddish-pink colour pork which is preferred by consumers, we suggest that producer produces the properly adjusted post-mortem pH24 h, the high water-holding capacity and the high moisture content in pork.
AN141037Carcass and meat properties of six genotypes of young bulls finished under feedlot tropical conditions of Mexico
Studying the carcass and meat properties of young bulls finished under feedlot temperate conditions of Mexico is very important for meat consumers. Therefore, the effect of six genotypes in Mexico on carcass and meat characteristics of young steers finished under feedlot conditions was tested. Results showed that the crossbred genotypes had better feedlot performance and carcass characteristics.
AN15142Effects of nanoparticle chromium on chromium absorbability, growth performance, blood parameters and carcass traits of pigs
Because trivalent chromium is difficult for animals to absorb, we used nanosize trivalent chromium to evaluate chromium absorbability in pigs. The study included Control, CrCl3, chromium picolinate (CrPic), NanoCrCl3, and NanoCrPic groups. The result shows that nanosize chromium could increase chromium absorbability in pigs. The absorbability of the NanoCrPic was the highest and increased serum and longissimus muscle chromium content.
The peer-reviewed and edited version of record published online before inclusion in an issue
AN16012Improving forage nutritive value and botanical composition in a natural grassland using different grazing methods and herbage allowances
The management of natural grasslands is crucial to increase meat production and ranchers profitability. This study aimed at assessing winter management of natural grasslands using sheep; continuous stocking and 12% herbage allowance improved sward quality in spring. These results provide an important management tool for grasslands ranchers so as to improve sward quality during spring.
AN16747Impact of zilpaterol hydrochloride and soybean-oil supplementation on intramuscular fat, fatty acid profile and cholesterol concentration in the longissimus muscle of male hair lamb under moderate heat-stress conditions
Zilpaterol and soybean-oil effects on lipid composition of lamb meat were studied under moderate heat-stress conditions. From a human nutrition standpoint, meat lipid composition was not improved by using zilpaterol and soybean oil. New strategies to nutritionally improve the lamb meat lipid profile should be explored.
AN16539Effects of drinking saline water on food and water intake, blood and urine electrolytes and biochemical and haematological parameters in goats: a preliminary study
The present study examined the capacity of young male goats to tolerate high levels of salinity in drinking water without harmful effects to their physiology. It seems that goats are better adapted to sustain their lives and remain productive in regions where fresh drinking water is scarce and of high salt concentration, thus limiting the presence and productivity of other herbivores. Subsequently, this raises considerations on the sustainable management of these lands and the capacity of these regions to support a conventionally calculated number of livestock units (LU), irrespective of animal species used.
We investigated the effect of shearing at 50 days of gestation on ewes grazing in improved pastures, on the vigour of lambs at birth, liveweight at birth and weaning weight. Early shearing coincides with the timing of development and growth of the placenta. Early shearing positively improved birthweight and weaning weight of individual and twin lambs. The twin lambs were more vigorous, which improved the rate of survival at birth. Therefore, shearing at 50 days of gestation can become a useful tool for sheep farmers.
AN16677Feeding antioxidant vitamin and vegetable oils to broilers: vitamin E reduced negative effect of soybean oil on immune response and meat lipid oxidation
Chicken meat consumption has increased considerably worldwide due to its low fat content; however, it contains a high amount of polyunsaturated fatty acids that make it susceptible to oxidation. The source of lipids in poultry diets could affect carcass fat composition and increase the need for antioxidants. This study demonstrates higher lipid oxidation in stored meat of broilers fed soybean oil than canola oil in the diet. Dietary vitamin E supplementation reduced meat lipid oxidation; however, vitamin C was ineffective at preserving meat against oxidative damage.
AN16767Growth performance, digestibility, haematology, biochemistry, and some humoral immunity blood parameters of broiler chickens fed different levels of Boswellia serrata resin
In animal production, herbal medicines that have already been tested in alternative human medicine are commonly used. This study demonstrated that a 2% and 2.5% addition of the Boswellia serrata resin in the diets can be used to improve haematological and biochemical blood parameters and receive good quality carcass. However, no clear impact of Boswellia serrata resin on humoral immunity was found. The Boswellia serrata resin can be efficiently used in chicken diets as a phytobiotic.
AN16746Physicochemical changes of semimembranosus muscle during the processing of dry-cured ham from Celta pig. Effect of crossbreeding with Duroc and Landrace genotypes
Crossbreeding is one of the main strategies to improve the meat quality of different dry-cured meat products. It is well known that lean/fat ratio and fat deposition in pigs is largely conditioned by the pig breed employed. In this study, hams obtained from crossbreeding pigs presented higher intramuscular fat than pure line hams. This is a positive point because intramuscular fat affect the juiciness and tenderness. As a general conclusion, the crossbreeding of Celta pigs allows us to improve the quality of dry-cured hams.
AN16574Effect of supplementing milk replacer with aromatic oregano (Oreganum onites L.) water on performance, immunity and general health profiles of Holstein calves
In recent years, restricting or prohibiting the addition of antimicrobial substances in diets has led to investigation into the use of plant extracts as feed additives. Therefore, the objectives of this study were to determine the effects of aromatic oregano (Oreganum onite L.) water on performance, immune system and general health of Holstein calves. The results of this study show that the natural additive of aromatic oregano water could be used successfully and safely in milk replacer to improve the overall performance of calves.
AN16540Impact of dietary Moringa oleifera leaves on intestinal pathogenic load and histological structure of growing rabbits raised under heat-stress conditions
Heat stress is a major problem for rabbits, which causes negative effects on the animal’s health that can extend to death. Natural antioxidants, such as moringa leaves, could be used as a dietary growth promoter for rabbits, helping to face problems induced by heat stress. The improvement of rabbits’ intestinal health encourages researchers to discover the other beneficial impacts of moringa leaves.
AN16390The influence of housing and feeding systems on selected fattening and slaughter parameters of finishing pigs with different genotypes
Housing and feeding systems affects the fattening and slaughter parameters of finishing pigs with different genotypes. Considering the selection of appropriate production technology of finishers should be well recognised for each solution. The best results in a study population were achieved for four-ways crossbreeding finishers on slatted floors and fed by liquid feeding.
AN15874Fermentation quality, in vitro digestibility and aerobic stability of total mixed ration silages prepared with whole-plant corn (Zea mays L.) and hulless barley (Hordeum vulgare L.) straw
Fermenation and aerobic stability is an important issue for total mixed ration (TMR) silage because of its low moisture and high nutrition. This study improved fermentation quality and aerobic stability of TMR silages by the combination of L. plantarum and ethanol. The result could provide a theoretical basis for selection of additive in TMR silage.
The intensity of grazing management required for optimal animal production in native grasslands of south-eastern Australia has been debated. This paper describes how the intensity of grazing management influenced lamb production per head and per hectare. While continuous grazing had higher production per head than 4- and 20-paddock rotational grazing, more ewes were run in the 20-paddock system to maintain similar production per hectare to continuous grazing.
AN15861Increased production and cover in a variable native pasture following intensive grazing management
The appropriate intensity of grazing management to improve pasture production and to sustain native species composition is still debated. This study found increasing the intensity of grazing management resulted in higher herbage mass, growth and ground cover of pastures, while landscape position largely influenced pasture composition. Increasing the intensity of grazing management may help limit the degradation of pastures.
AN15856Designing a grazing-system experiment for variable native pastures and flexible lamb-production systems
Grazing systems represent complex interactions between animals, pastures, soils, climate and management. This paper describes the process used to characterise the potential productivity of variable native pastures, and the development of flexible systems. Incorporating spatial variability into the design, and flexibility into the management of grazing experiments, should lead to results that are better aligned with commercial grazing practices.
AN16801Sperm quality, and morphology and apoptosis of germinal epithelium cells of ram lambs receiving water of different salinities
The ground water from semiarid areas has been an alternative source of drinking water for the small ruminants; however, it shows a wide variation in the concentration of total dissolved solids (i.e. salinity). Consequently, water salinity could affect apoptosis in testicular seminiferous tubules and, further, semen quality in ovine species, which was confirmed in the present study. Therefore, high-salinity water should be avoided because it increases the damage to the germinal cells of ram lambs.
AN16712Meta-analysis of genetic-parameter estimates for reproduction, growth and carcass traits in Nellore cattle by using a random-effects model
Different studies have reported contradictory heritability and genetic-correlation estimates for reproduction, growth and carcass traits in purebred Nellore cattle. The motivation for the present study was to remove the heterogeneity between published estimates and summarise the results through meta-analysis using a random-effects model.
AN16673An assessment of sire-breed effects on carcass and meat quality traits of lambs at the ages of 40 and 100 days from Comisana ewes crossed with Suffolk or Bergamasca rams
Lamb meat production is a worldwide phenomenon. Improving the production and profitability of sheep farms is an excellent way of guaranteeing their subsistence. Crossbreeding dairy ewes with meat rams enhances productivity without affecting meat quality.
A lot of effort has been made by the Thai government and cooperative organisations to develop dairy farming in Thailand. We estimated genetic parameters and breeding values for milk production and milk composition from three government dairy cattle farms in Thailand. The results suggest that selective breeding using estimated breeding values can be used to enhance the performance of Thai cattle.
AN16603A comparison of the effects of post-mortem aging on breast meat from Cobb 500 and Hubbard ISA broilers
This study compared the characteristics of the breast meat from Cobb 500 and Hubbard ISA broilers and evaluated the effect of aging for up to 7 days on meat quality. Even though meat from Hubbard ISA broilers is less tender, its use may be beneficial to the poultry industry due to the lower production of exudate. Moreover, it has higher levels of PUFA, which is beneficial to human health. Aging for 3 days at 2°C is sufficient to tenderise and add value to free-range meat.
An investigation to determine whether heifers can be trained to respond to a sound to seek out a feed reward has shown promising results. The heifers were more likely and quicker to respond to the sound when they were called as a group rather than as individuals. The study suggests that voluntary trafficking could be encouraged through animal-mounted calling devices.
There is a continuing evolution of feeding systems in Australian and New Zealand dairy industries. This review summarises research into optimising feed efficiency focussing on growing more forage on farm, increasing its utilisation and more efficient use of supplements. Simply growing more feed on farm can no longer be a sole objective; farming must also be done with a view of satisfying public expectations around environmental stewardship.
Liveweight (LW) is a key measurement for livestock owners but most farmers in sub-Saharan Africa have to use heart girth measurements to estimate LW because they cannot access scales. Most equations used to estimate LW are population specific and have large prediction errors, but using several large databases we developed an equation with less error, which can be used in a wider population. A stronger, widely applicable equation to estimate LW of African cattle will enable farmers to make better livestock management decisions.
AN16719Effects of dietary antioxidant supplementation of steers finished with 30% wet distillers grains plus solubles on fatty acid profiles and display life of strip loins
Feeding distillers grains in beef feedlot diets decreases shelf-life, while supplementing antioxidants may mitigate such effects. This research evaluated the effects of feedlot diets containing distillers grains and different antioxidants on the shelf-life of retail-displayed beef. Results showed that supplementing feedlot cattle vitamin E alone or with a synthetic antioxidant was effective in shelf-life extension, which could provide long-range improvement in beef quality.
AN16438Offsets required to reduce the carbon balance of sheep and beef farms through carbon sequestration in trees and soils
This study demonstrates that sheep and beef enterprises can reduce or entirely offset their greenhouse gas emissions by storing carbon in trees. The carbon balance was calculated for enterprises with different stocking rates and levels of tree cover, and an intensively stocked case study farm was also analysed. Most stocking rates were carbon positive with >20% tree cover. This study provides an important reference point for farmers, researchers and policy analysts to estimate the carbon balance of farms.
AN16452Evaluating the ability of a lifetime nutrient-partitioning model for simulating the performance of Australian Holstein dairy cows
The present study demonstrated the capability of a lifetime nutrient-partitioning model for simulating genetic variation in production potential of Australian Holstein cows. The model could accurately predict the performance curves of bodyweight, milk protein and milk lactose concentration, while milk yield, milk fat concentration and body condition score were satisfactorily predicted, and the prediction of dry-matter intake was promising. It is suggested that the model can be further developed to simulate the effects of genetic and management strategies on production and efficiency of individual cows.
AN16524Perennial ryegrass breeding and the scaling issue: a review of system experiments investigating milk production and profit differences among cultivars
Whole-system studies comparing perennial ryegrass cultivars allow information from small plot trials to be validated, giving farmers confidence to invest in the use of new cultivars. A small number of whole-system studies have been published but results are not consistent. Despite the cost and complexity, there is a need for whole-system studies to be undertaken to explain where benefits in animal performance from improved cultivars come from.
AN16487The economic value to dairy systems of genetic gains in the nutritive value of perennial ryegrass in grass–clover pastures
Perennial ryegrass breeding efforts have focussed on improving pasture feed quality; however, the gains in farm profitability that this has delivered are not known. The feed quality characteristics of 24 perennial ryegrass cultivars were compared; genetic gains in whole-pasture feed quality have been delivered to dairy farmers through the development of later-flowering and tetraploid cultivars. The gains in pasture feed quality have the potential to deliver economic benefits in the range of NZ$54 to NZ$232/ha.year to New Zealand dairy farmers.
The present study investigated the influence of a quality-grading system, demographic information and consumption preferences on consumer willingness to pay (WTP) for sheep meat. Eating quality was defined by four grades developed by the Meat Standards Australia (MSA) sheep-meat grading scheme. Results clearly showed that consumers were willing to pay more for sheep meat as eating quality improved. Robust results for the impact of demographic and consumption preferences on WTP were limited to consumer age, occupation, income level and the interaction between MSA grade and consumer age.
AN16250Nutrient utilisation in grower pigs fed a protein concentrate blended with sweet potato roots either boiled or ensiled with or without vines
Sweet potato (SP) provides high levels of starch but the dietary fibre lowers its feeding value to growing pigs. Ensiled or boiled SP roots were of similar feeding value but including SP vines lowered the energy use and growth of crossbred pigs. Ensiling SP forage is advantageous to tropical feeding systems but for growing pigs using vines should be controlled.
Nuisance flies are important arthropod pests in cattle feedlots, with the potential to cause production loss and health impacts on livestock, workers and surrounding communities. Population models were developed for fly abundance and showed that fly numbers could be predicted using time-of-year and rainfall. The models provide a useful tool for optimising the timing of fly-control treatments, such as insecticide or biopesticide applications, adding to the effectiveness of integrated pest-management programs for the control of nuisance flies in feedlots.
AN16097Fitting of pH conditions for the study of concentrate feeds fermentation by the in vitro gas-production technique
Estimation of microbial fermentation of concentrate feeds for ruminants from the in vitro gas-production technique is biased by the differences in incubation pH, established at ~6.5 when rumen pH actually drops below 6.0 in this type of diets. Adjustment of incubation pH by reducing the buffering of the medium is a simple way to overcome this problem in short-length incubations.
This study determines the relationship of element content with elements of blood, soil, range forage and animals ration. The influence of protein or energy supplementation on the yield and its easy adaptation to various rearing environments was investigated. This is a new correlational perspective on the factors that can affect cashmere quality.
Lactation benefits the bovine offspring, but also implies numerous physiological challenges for the dairy cow. The present review addresses the latest findings on metabolic and endocrine adaptation mechanisms to lactation, their interaction with the offspring and the maternal immune competence, and considers the specifics of pasture-based systems. Recent developments in precision livestock farming technology are capable of detecting health disorders early and maintaining animal well-being.
AN16458The effect of pre-graze mowing on milk production of dairy cows grazing grass–herb–legume pastures managed under contrasting spring defoliation regimes
Strategies to increase herbage dry matter (DM) production are sought for dairy systems. Compared with perennial ryegrass pasture, a diverse pasture containing legumes and herbs have different grazing requirements that can affect regrowth, persistence, and nutritive value. Options to manage diverse pastures for improved pasture production and animal production were investigated using conventional grazing or lax grazing. Using lax grazing to manage diverse pastures in spring is unlikely to provide milk yield benefits.
AN16544Effects of pasture allowance on milk production of dairy cows offered increasing amounts of partial mixed rations in spring
Cows were fed diets comprising three different pasture allowances with one of four different amounts of mixed ration. Cows grazing the highest pasture allowance had greater intakes of pasture, but they did not have higher yields of milk than cows on more modest pasture allowances. These results will enable farmers to better optimise feeding systems that combine both pasture and mixed ration.
Lamb mortality is an important production and welfare issue worldwide. In this paper we demonstrate how litter size affects the maternal genetic contribution to lamb survival and compare alternative approaches to defining the ewe rearing ability trait, ignoring or accommodating variation in lamb survival due to litter size. The accuracy of genetic evaluation for rearing ability may be improved if the impact of litter size on lamb mortality is considered.
AN15564Effects of grain level on lamb performance, ruminal metabolism and leptin mRNA expression in perirenal adipose tissue
Feeding lambs in feedlot are based on high proportions of grains in the rations. However, the grain level required to obtain the best lamb performance is unknown. The experiment conducted allowed us to identify that 60% grain is the optimal level. Grain finishing with higher levels involves risk in the health status of lambs.
AN16161The use of energy-protein supplement increases performance of high-yielding dairy cows and improves health-promoting properties of milk
We can increase the content of milk components desirable from the human health point of view by feeding lipid additives to cows. The aim of the study was to determine the effects of a special supplement on health-promoting properties of milk. We discovered that the supplement had a beneficial effect on milk properties, and produced milk that may serve the role of functional food for people in the future.
AN16788Use of barley crops, and combinations of lucerne and Wimmera grass, as pasture for grazing sheep in the semiarid zones of Spain
Feeding represents more than half of the total production cost of sheep meat production, hence the search for a cheaper source of feed seems an urgent need. Integrating sheep in cropping systems might be part of the solution, and the results showed that using permanent sown lucerne, self-sowing Wimmera ryegrass and barley all year round would be an adequate feeding strategy. This practice would reduce production costs and have positive environmental implications.
AN16570Determining the appropriate selection index for Rayeni Cashmere goat under pasture-based production system
Rayeni Cashmere goat is raised by nomads in Kerman province of Iran. Nomads have no guidelines to establish a breeding program in their herds. The aim of the current study was to investigate breeding goals and find the best selection index for Rayeni Cashmere goat. The most appropriate selection index for this breed was determined to improve nomad income by genetic improvement of Rayeni Cashmere goat epopulations.
Spring-calving pasture-based dairy systems have the flexibility to milk the cows for longer into autumn if there is sufficient feed or if it is profitable to buy supplement. To prevent negative impacts on the following year’s performance, farmers must ensure that cows reach a target body condition by their next calving date, and that there is sufficient pasture available for the following year. Possible options were modelled with a decision-support tool to allow farmers and advisors to interactively consider the profitability of those options, while ensuring no negative impacts on the following year.
Australian and New Zealand dairy farmers have been increasingly exposed to volatility in market prices as well as climate variability, and changing regulation and consumer demand. Systems research plays a key role in testing different options for farmers to maintain profitability despite these challenges. There is need for research to fore-sight future risk and challenges, as well as opportunities, and working collaboratively with dairy farmers to increase knowledge transfer and adoption of positive research outcome.
AN16290Effect of biochar, zeolite and bentonite feed supplements on egg yield and excreta attributes
Low rates of feed additive can improve poultry production and excreta characteristics. Biochar, zeolite and bentonite added to layer poultry rations at low rates resulted in improved feed conversion rates, especially when birds were challenged with fungus contaminated feed. These results may reflect an impact of these feed amendments on gut ‘health’ (microbiology or absorption of feed toxins).
AN16521Administration of a live attenuated Salmonella vaccine using an inactivated oil-emulsion vaccine as a vehicle for commercial chicken flocks
The combination of a live vaccine into an inactivated vaccine provides convenience to poultry farmers in administration. This study evaluated the survival and effectiveness of the live vaccine when administered this way. The live vaccine had reduced viability over time and the birds showed a reduced immune response to it when adminsitered this way.
AN16346Influences of dietary supplementation of peanut skin powder (Arachis Hypogaea) on growth performance, carcass traits, blood chemistry, antioxidant activity and meat quality of broilers
Because of bad repercussions from using antibiotics and other chemical preparations, there was a dire need for natural alternatives. Our work aimed to investigate the impacts of using peanut skin powder on growth and health of broilers. Peanut skin powder lowered the amounts of carcass fats and minimised blood cholesterol, creatinine and urea, which means healthy chicken meat was gained.
AN16440Quantifying dairy farm nutrient fluxes and balances for improved assessment of environmental performance
Excess nutrients are challenging the long-term sustainability of grazing-based dairy farming. We have developed an online tool that quantifies nutrient fluxes, balances and efficiency, as well as feed and milk production performance at the whole-farm level. This standardised assessment provides dairy farmers, advisors and industry and policy analysts with the ability to improve environmental performance and develop industry-wide goals.
Reproduction can disrupt the oxidant–antioxidant balance because of the considerable capacity for reactive oxygen species generation during steroidogenesis and during the formation and regression of ovarian structures. A deeper characterisation of the roles that redox balance plays in the control of reproductive physiology will allow the development of strategic dietary antioxidant interventions that can significantly reduce reproductive wastage in domestic animals.
AN16475Herbage production, botanical composition and survival of perennial ryegrass- and tall fescue-based swards in simple and diverse species mixtures in a dryland environment
Will increasing species diversity in perennial ryegrass- or tall fescue-based swards benefit herbage production on dairy farms? Different species mixtures were compared to determine whether including other forage species in traditional grass–clover swards would improve total herbage production or production at key times during the farming season. Perennial ryegrass-based swards produced more than did tall fescue-based swards, but increasing sward diversity did not consistently improve production and was likely to be related to climate. While some species showed potential to improve production, this must be balanced with considerations of how increasing sward species diversity affects sward management.
The use of tropical legume crops has been increasing to recover degraded pastures and to improve the animal performance. Feeding beef cattle with tropical legumes is a common practice around the world, but the use of these crops preserved as silage has not been extensively evaluated. Stylosanthes cv. Campo Grande silage showed the potential to be used in diets for beef cattle in tropical conditions, because it resulted in similar productive performance of the animals in comparison with corn silage.
AN16288Production responses in young bulls fed glycerin as a replacement for concentrates in feedlot diets
To meet global demand, increases in meat production are essential. Although conventional feed costs may limit the feedlot finishing of beef cattle, this can be circumvented by the use of agro-industrial by-products. The use of crude glycerin in cattle diets can increase animal performance and reduce the cost of feeding.
AN16455Herbage dry-matter yield and nitrogen concentration of grass, legume and herb species grown at different nitrogen-fertiliser rates under irrigation
An important goal in New Zealand dairy systems is to increase production while achieving environmental targets associated with lower nitrate leaching from soils. A major contributor to leaching is the amount of nitrogen in the animals’ diet; therefore, one approach is to identify pastures that grow more and also have a lower nitrogen content. Results found there were no benefits in using herbs instead of grasses for reducing nitrogen intake in livestock in an irrigated Canterbury environment.
AN15712Efficacy of hydrate sodium calcium aluminosilicate and yeast cell wall to ameliorate the toxic effects of aflatoxin in ducks
A worldwide shortage of grain is resulting in large numbers of poultry birds being affected by aflatoxin, which is a toxin produced by certain types of mould. The aim of our research was to evaluate Fixar® Viva Dry, compounds of silicates and yeast cell wall components, as a dietary supplement that could absorb the aflatoxin from meat producing ducks. Our results showed that using this dietery supplement could improve the mortality rates of poultry worldwide and that the economic-loss index could be improved in that sector.
AN16709Diurnal variation in urine nitrogen and creatinine concentrations from lactating cows grazing ryegrass-dominant pasture in autumn and late spring–summer
Estimating the amount nitrogen (N) excreted in urine patches on grazed pasture requires samples of urine. This experiment identified the diurnal variation in urine N concentrations, which were lowest at milking times and highest mid-morning or early evening. For accurate estimates of the daily mean urine N concentration, sampling should include times of the day that are representative of both low and high concentrations.
AN16687Influence of low-protein and low-amino acid diets with different sources of protease on performance, carcasses and nitrogen retention of broiler chickens
There are some nutritional strategies that can be used to improve poultry performance and public health like supplementation of commercial enzymes to low-protein diets. The aims of this study were to evaluate the impacts of commercial enzymes supplemented into low-protein diets on performance and economic aspects of broilers. Using different commercial enzymes in low-density diets can partially improve performance and economic aspects in broilers.
AN16616Using ultrasound to derive new reproductive traits in tropical beef breeds: implications for genetic evaluation
Ultrasound has enabled the identification of heifers genetically superior for the ability to reach sexual maturity and become pregnant earlier in the breeding season, attributes that profoundly impact lifetime reproduction. Research methods to identify superior individuals have laboriously involved multiple ultrasound examinations, so the current research adopted previous methodology to enable identification of superior breeding females using a single ultrasound examination. Adoption of ultrasound technology by commercial beef producers to measure fertility in their herds will be enhanced if a simple, robust system is presented.
AN16457The effect of dairy farm intensification on farm operation, economics and risk: a marginal analysis
Do new buildings and more cows make a New Zealand dairy farm more profitable? Using basic economic principles, and recent milk prices and farm costs, the present study found that limited intensification can improve profitability, but making a farm highly intensive seldom would. This work is important because of growing economic and environmental constraints on dairy farming.
AN16196Environmental impacts and resource use from Australian pork production determined using life cycle assessment. 2. Energy, water and land occupation
This study completed a life cycle assessment of energy, water and land occupation from pork production, covering supply chains and the national herd. Impacts arose predominantly from feed production, highlighting the importance of system efficiency, and particularly the feed conversion ratio for reducing resource use and environmental impacts. Changes to housing and improvements to manure management offer substantial opportunities for reducing the resource use intensity of pork.
AN16514Evaluation of an activity and rumination monitor in dairy cattle grazing two types of forages
The ability to measure, monitor and detect changes in the behaviour of cattle will assist in improving individual cow health and performance. This study tested the accuracy of a new generation of the SCR HR-LDn activity and rumination monitoring system for grazing cows. The results showed that the device quantified the time cows spent ruminating, grazing and resting with high to very high levels of accuracy.
AN16601Effect of herbage allowance on productive and reproductive responses of primiparous beef cows grazing on Campos grassland
The Campos region is the largest biogeographic unit of native grasslands in South America and cow-calf operations primarily graze this grassland. We studied the effects of herbage allowances of 2.5 (low) and 4 (high) kg dry matter/kg liveweight in primiparous beef cows over the entire production cycle on forage mass, cow body condition score, cow liveweight, stocking rate, postpartum anoestrus, probability of pregnancy and calf weight at weaning. The forage mass, reproductive and productive responses were improved in high herbage allowances over 2 years with different patterns of rainfall.
AN16548Genetic evaluation of bodyweight, scrotal circumference, and visual appraisal scores in Bos indicus cattle
Estimates of genetic parameters are broadly studied in Brazil for Bos indicus animals, particularly in Nellore cattle, but conversely, for Guzerat, another B. indicus breed, no studies were performed. A study was designed to estimate the genetic parameters and trends for body conformation measures. The magnitude of direct heritability estimates ranged from moderate to high, and genetic and phenotypic trends indicate favourable changes during the evaluated period.
AN16018Genome-wide association studies, meta-analyses and derived gene network for meat quality and carcass traits in pigs
Genome association studies for meat quality and carcass traits have identified genes and markers of major relevance for modern pig breeding industries. We have validated significant markers for meat quality and carcass traits with meta-analysis. Further, we developed gene network from GWAS that identified key transcription factors, gene-gene interactions and molecular pathways contributing to understanding the molecular genetic mechanisms underlying these traits in pigs.
AN16352Effects of olive-cake supplementation on fatty acid composition, antioxidant status and lipid and meat-colour stability of Barbarine lambs reared on improved rangeland plus concentrates or indoors with oat hay plus concentrates
Medicago arborea and olive cake can be used in sheep diets as alternative feeds to reduce cost production and/or improve meat quality. Effects of olive-cake supplementation on meat quality of indoor and grazing lambs were studied. Grazing on rangeland containing Medicago arborea improved nutritional meat quality and stability of lipids. Olive cake supplementation did not have any effects.
AN15818Identification of heat stress-susceptible and -tolerant phenotypes in goats in semiarid tropics
Heat stress is one of the major challenges for sustaining livestock production globally. Therefore, it is necessary to devise strategies for amelioration of heat stress by selecting genetically resilient animals for optimum productivity. The present study identified heat stress-tolerant and heat stress-susceptible individuals on the basis of heart rate and respiration rate. The selection method can be utilised for selecting animals towards improved resistance to heat stress and managing the livestock for better production and welfare.
Essential oils have many possibilities as feed additives in livestock as natural alternatives to replace other chemical additives. Consumer acceptability of meat from these types of natural additives is important in order to increase the knowledge about these promising feeding systems. Essential oil additives in the diet of crossbred beef cattle did not negatively affect consumer meat acceptability scores or product perception.
AN16838Social rank and reproductive performance in a herd of farmed red deer females (Cervus elaphus)
Hierarchical relationships between individuals of several ruminant species result in differential access to resources and thus in advantages in reproductive performance of those of higher social rank. Under captive conditions with high food availability as in the present experiment, reproductive traits of red deer females were unrelated to social rank. These results reaffirm the concept that most ruminants have plastic responses to environmental conditions, and thus, not necessarily social structure affects their reproductive performance.
AN16646Balancing water-quality threats from nutrients and production in Australian and New Zealand dairy farms under low profit margins
There is a wide range of nitrogen and phosphorus losses from Australian and New Zealand dairy farms that could impair water quality. To meet voluntary and regulatory requirements to decrease nitrogen and phosphorus losses we tested a generalised approach to mitigation (priority given to those that are easy to implement) and found that phosphorus could be mitigated quite cheaply, but nitrogen reductions required more measures, some of which are costly.
AN16523Effects of aging on characteristics of breast meat from free-range broiler hens at 12 or 70 weeks of age
Little is known about the acceptability of free-range broiler hen meat. This study evaluated the effect of broiler age and the aging process on the properties of broiler hen breast meat. Its use is beneficial because it has lower storage and cooking losses and lower polyunsaturated fatty acid concentration, which makes it less vulnerable to rancidification. Aging for at least 3 days at 2°C is satisfactory to tenderise the breast meat from free-range broiler hens.
Moisture deficit reduces growth of perennial ryegrass in many New Zealand dairy pastures. In a semi-controlled glasshouse study, we found the effects of previous moisture deficit on four ryegrass cultivars were greatest during the recovery period when moisture stress was alleviated. Results imply that avoiding overgrazing immediately after drought is just as critical for recovery as is management during a drought.
AN16308Comparison of bacterial populations in bedding material, on teat ends, and in milk of cows housed in compost bedded pack barns
The management of compost bedded systems aims to provide a clean and comfortable place for cows. However, unappropriated management can increase bedding moisture, which may reflect on cow’s health and milk quality. This study proposed to understand the relationship between bacterial populations on bedding pack and bacterial population found on teat end surface and in milk. In the end, we concluded that hygiene score was not an efficient tool to estimate bacterial population on teat end and milk.
Pastoral livestock-production systems are under scrutiny, with farmers being required to reduce environmental impacts and to enhance biodiversity and animal welfare. Creating synergies between grazing decisions by animals and farmers offers greater benefits to the animal, the farm, and the environment than do simple management approaches based on managing for single components of the system. We envisage a more holistic approach to managing grazing based on recent advances in the understanding of the nutritional ecology of grazing animals.
AN16162The effect of nitrate supplementation on arterial blood gases, haemoglobin fractions and heart rate in Bos indicus cattle after exercise
Nitrate salts are recommended to reduce methane emissions in extensively grazed cattle. After treatment with nitrate salts for 7 days and walking 3 km Bos indicus steers demonstrated a reduction in the oxygen carrying capacity of their blood and an elevated heart rate. The recommended dose rate of nitrate salts to reduce methane emissions in cattle will create a hypoxaemia in cattle.
The cows exposed to a sudden increase in temperature displayed the characteristic physiological responses of short-term heat acclimation. These results indicated that the conditions imposed on the cows in the controlled-climate chambers were sufficient to induce moderate heat-stress responses and adversely affected production in the lactating dairy cow. Following the heat challenge in controlled-climate chambers, the cows experienced a period of metabolic recovery as there was a delayed effect between the return to baseline feed intake and the return to baseline milk yield.
AN16715Pasture productivity and quality of Urochloa brizantha cultivar Marandu evaluated at two grazing intervals and their impact on milk production
Chronologically fixed periods are used to define grazing intervals in the management of tropical grasses with rotational stocking; however, the growth rate of the grass is influenced by edaphoclimatic conditions. The aim was to examine the effect of variable grazing intervals, defined when the canopy reached 95% light interception. Milk yield per area increased ~28% when variable grazing intervals were utilised. This demonstrates that management strategies that respect the morphophysiological traits of forage species can be more productive.
AN16481Changes in nutritive characteristics associated with plant height, and nutrient selection by dairy cows grazing four perennial pasture grasses
In perennial ryegrass pastures, it is well established that dairy cows select a diet that differs from the nutritive characteristics of the pasture on offer, but less is known about this for other temperate perennial grasses. In the present study, cows selected a diet higher in crude protein than the pasture on offer, but less so for other nutrients, and this was correlated with the vertical distribution of nutrients within the plant. These results assist in developing grazing guidelines for cocksfoot, tall fescue and prairie grass.
AN16479Partitioning of dietary nitrogen in response to feeding cereal grain supplements to dairy cows during four periods of an extended lactation
In Australia, there is interest in milking cows for longer than the traditional 300 days. During a 567-day experiment with lactating dairy cows, the partitioning of nitrogen (N) in the second year of an extended lactation was different from that in the first year, N-use efficiency was negatively related to N intake and days in milk, and adding grain to the diet increased total N intake but decreased N-use efficiency.
AN16477Can concentrations of trans octadecenoic acids in milk fat be used to predict methane yields of dairy cows?
Recent research from Europe has suggested that concentrations of trans octadecenoic acids in milk fat may be used to predict methane emissions from dairy cows. Data from seven experiments involving 23 different diets and 220 observations on milk fatty acids were examined for potential to predict methane emissions. It was concluded that concentrations of trans isomers of C18:1 have limited potential to predict methane emissions, yields or intensities of dairy cows.
AN16511Whole-tract digestibility and nitrogen-use efficiency of partial mixed rations with and without canola meal
Increasing the amount of crude protein in a dairy cow’s diet can increase intake and milk yield, yet the fate of the extra protein and the nitrogen-use efficiency has not been quantified. In the present experiment, the addition of canola meal, as a source of extra protein, increased intake but resulted in poorer nitrogen-use efficiency and more nitrogen being excreted. This indicated a need to find a balance between the benefits of feeding extra protein and the cost of wasted nitrogen.
AN16582Growth and reproductive traits of F1-generation transgenic goats for human granulocyte-colony stimulating factor
The randomness of transgene insertion in genetically modified animals by the microinjection technique may compromise the health and welfare of animals. We demonstrate in this work that insertion of the human granulocyte-colony stimulating factor (hG-CSF) transgene in the two lines of transgenic goats does not compromise the health of animals. This information is an important step in the use of animals as bioreactors for the production of large-scale hG-CSF.
Mycoplasma bovis is a major disease-causing agent in cattle causing significant economic losses to the cattle industry. Due to the lack of effective treatment measures, early detection of this disease agent in a cattle herd is paramount. This review focuses on the past and present improvements in the diagnosis of disease caused by Mycoplasma bovis in cattle.
AN16119Effects of Bacillus amyloliquefaciens LFB112 in the diet on growth of broilers and on the quality and fatty acid composition of broiler meat
Consumers are becoming increasingly interested in food containing a high concentration of polyunsaturated fatty acids (PUFA), which are considered as functional ingredients to prevent cardiovascular disease and other chronic diseases. In order to achieve desirable meat, we have investigated the effects of Bacillus amyloliquefaciens LFB112 in the diet on the growth of broilers and on the quality of broiler meat and found that dietary supplementation of B. amyloliquefaciens LFB112 enhanced average daily gain, average daily feed intake and improves meat colour and fatty acid composition of meat from broilers. Our study showed that PUFA composition of meat from broilers was profoundly affected by diet and can be approached, at least in part, from a microbial point of view, suggesting that intake of meat from broilers fed a B. amyloliquefaciens-supplemented diet might exert protective effects on cardiovascular disease.
Alternative methods to improve performance and carcass traits, considering animal welfare. The aim was to compare surgical castration and immunocastration in beef cattle raised on pasture. Immunocastration can replace surgical castration and is an efficient method to improve carcass traits. The castration methods improve meat quality and carcass finishing; however, intact animals present greater production capacity.
Greater knowledge of the diet selection of animals managed within grazing systems is essential to enhance animal performance. The diet selection and performance of sheep grazing a native pasture was assessed and a major driver of selection – the green : dead ratio (or greenness) of herbage – was identified. Monitoring the greenness of a pasture may provide a management trigger to enhance the production of animals within a rotational grazing system, in particular during periods of higher requirements.
Dairy cattle are a significant source of methane and nitrous oxide gases, which are both potent greenhouse gases (GHGs). The objective of the present study was to approximate GHG emissions using realised and predicted genetic selection responses for biological traits in the Australian national breeding objective. We estimate that genetic improvement of dairy cows in Australia has helped reduce the carbon footprint of milk production and will continue to do so in the future, albeit at a slightly lower rate.
AN16528Factors explaining the incidence of breech strike in a Mediterranean environment in unmulesed and uncrutched Merino sheep
Breech strike cost the Australian industry more than AU$200 million per year. Factors responsible for an increase in breech strike were investigated in unmulesed Merinos in a production system where no chemical preventative treatments were applied. Dags in uncrutched sheep and tail wrinkle in crutched sheep were the two most important predisposing factors for breech strike but a large proportion of the variation in breech strike in unmulesed and uncrutched sheep could not be explained.
AN16013Variation in instrumental meat quality among 15 muscles from 14-month-old sheep and its relationship with fibre typing
Muscle fibres are the main components of meat and their characteristics are crucial for meat quality. We studied the associations between fibre typing and meat quality across 15 young-sheep muscles and found that although fibre diversity may explain, at least in part, intermuscular differences in meat quality, these associations can also slightly vary in sense among different contractile–metabolic groups of muscles. The present study has contributed to a better understanding of the influence of muscle fibre types on intermuscular meat-quality variation.
The living conditions we provide for farm animals are of increasing public concern. This paper explores different approaches to addressing public criticisms, including enacting ‘ag-gag’ laws and ‘educating’ the consumer. We conclude that livestock industries needs to develop methods of meaningful two-way engagement with concerned citizens, invest in research to better understand the values of different stakeholders and experiment with alternative practices that resolve concerns.
AN16541The nutrition of grazing ewes during pregnancy and lactation: relationships between herbage, supplement and milk intakes, and ewe and lamb liveweight and body composition
We investigated the effects of stocking rate and supplementary feeding on the performance of grazing ewes in pregnancy/lactation, and on their lambs. Both treatments had significant effects on intake and liveweight responses, but there were also marked effects of initial condition score and dentition score of ewes. In future work, more attention needs to be paid to these scores as important explanatory variables.
AN16108Genetic correlation between growth and reproductive performance of beef females depends on environment
Growth and reproductive traits of beef cattle are important economically and, therefore, are commonly included in selection indices. In tropical production systems, beef cattle are raised in highly heterogeneous environments. It has been shown that genetic associations between growth traits and reproductive performance are dependent on the production environment; thus, the genotype by environment interaction is important for genetic evaluations and can affect selection of these traits.
AN16061Effect of growth path on the performance and carcass traits of Hereford steers finished either on pasture or in feedlot
There is no information available about how differences in growth rate before the finishing phase affect animal performance and carcass attributes of cattle finished under temperate conditions. The objective of the present study was to assess the effect of nutritional management during the rearing period on the performance and carcass traits of pasture-finished or feedlot-finished Hereford cattle. Nutritional feeding management during the first winter has a permanent effect on the growth, feed conversion traits, and carcass traits. However, the prevalence of these effects depends on the feeding system during the finishing phase of animals.
AN15884Effect of dietary sodium diacetate on growth performance, carcass characteristics, meat quality, intestinal pH and Escherichia coli of broilers
The organic acids that were regarded as substitutes for antibiotics have recently been applied to decrease the proliferation of acid-intolerant enteropathogenic bacteria. This research investigated the influences of dietary sodium diacetate on growth performance, carcass characteristics, meat quality, and intestinal pH and Escherichia coli count of broilers. Results suggest that dietary sodium diacetate could improve growth performance, meat quality and intestinal health of broilers.
AN16153Sheep death and loss of production associated with flystrike in mature Merino and crossbred ewes
Flystrike causes losses due to sheep deaths and loss of production. This study quantifies the loss of weight, condition, wool and lamb production in flocks in a wide range of regions of Australia. The results can be used to estimate losses due to flystrike and potential benefits of preventing strike or reducing its severity.
AN16441Feeding diets with fodder beet decreased methane emissions from dry and lactating dairy cows in grazing systems
Fodder beet contains high concentrations of readily fermentable carbohydrates. Feeding fodder beet to dairy cows might alter rumen fermentation and consequently methane emissions. Feeding fodder beet in pastoral systems at ~50% and ~20% of the diet of dry and lactating dairy cows, respectively, decreased methane emissions compared with feeding forage kale and pasture alone.
Grape marc is composed of the skins, seeds and stems of grapes after they have been pressed for wine, and has been shown to reduce methane emissions when fed to dairy cows. A range of grape marc samples were evaluated for their potential to reduce methane emissions if used as a feed additive for dairy cows. There was a wide range of results, but grape marc that had been sourced fresh proved to be the most promising.
AN16350Improving ruminal fermentation and nutrient digestibility in dairy steers by banana flower powder-pellet supplementation
Ruminal pH is a critical factor that could affect rumen fermentation efficiency; thereby, rumen buffer should be considered. Banana flower power-pellet could enhance rumen ecology and fermentation efficiency. This study suggests that banana flower powder pellet is potentially used as a rumen buffer agent for high-producing cattle, promising to replace sodium bicarbonate.
Improving our knowledge of the physiological characteristics of ovine species in stressful situations during the neonatal phase will be of great economic importance for livestock production. Breaking the ewe–lamb bond at different ages and for brief separation times triggers metabolic changes in young animals. The greatest physiological alterations occurred in the parameters of the youngest lambs, after a separation of 10 min from their mothers. Younger lambs suffered greater metabolic changes in contrast to older lambs.
AN16466Rumen degradability characteristics of five starch-based concentrate supplements used on Australian dairy farms
Rate and extent of starch degradation in the rumen is an important factor affecting milk production responses in high-yielding dairy cows. We compared starch degradation in the rumen of five concentrates relevant to Australian dairy farmers. Results showed that maize grain has the slowest rate of starch degradation, followed by sodium hydroxide-treated wheat and Maximize (a commercial pellet), with wheat and oat starch being rapidly degradable.
Feeding concentrates so that the marginal cost of extra feed closely matches the marginal revenue from extra milk produced should enable dairy farmers to feed supplements profitably. In the present study, a farm in northern Victoria was used to analyse the economics of tactical (short-term) and strategic (medium- to longer-term) decisions about concentrate feeding. The results show that making decisions about supplementary feeding using marginal analysis adds more to farm profit than making decisions on the basis of other criteria, such as feeding supplement for maximum milk production.
AN16707Early detection of clinical mastitis from electrical conductivity data in an automatic milking system
The ability of electrical conductivity to detect clinical mastitis is variable in automatic milking systems. This study has evaluated a range of indexes and algorithms created from quarter-level electrical conductivity data for early detection of clinical mastitis, but could not achieve the required accuracy. Incorporating other information related to milk yield may increase accuracy of detection and the ability to detect the early onset of mastitis.
AN16365Genetic relations and indirect response to selection based on indices for scrotal circumference, visual scores and weight gain in beef cattle
We showed the genetic and phenotypic correlations between economic traits and selection indices, besides the expected genetic gains. Selection for better body composition should provide increase in scrotal circumference and weight gain. The use of indices should result in a positively correlated response for indirectly selected traits. Higher genetic gains to visual scores are expected when the selection is based on the values of these indices.
AN16456Milk production and composition of dairy cows grazing two perennial ryegrass cultivars allocated in the morning and afternoon
Afternoon herbage allocation is a management to match herbage supply to the diurnal grazing pattern for dairy cows. We found that perennial ryegrass cultivars reacted differently to this management in terms of nutritive value and nitrogen-use efficiency of dairy cows. Therefore, pastoral dairy production systems would potentially benefit from afternoon herbage allocation using the right perennial ryegrass cultivar.
AN16128Influence of zeolite (clinoptilolite) supplementation on characteristics of digestion and ruminal fermentation of steers fed a steam-flaked corn-based finishing diet
Because of their sorbent properties and binding capacity with ammonia, natural zeolites may have application as feed additive in livestock industry. Our results indicate that zeolite supplementation of high finishing diets enhances ruminal fermentation and increases digestion.
AN16556Characteristics of carcasses and meat from feedlot-finished buffalo and Bos indicus (Nellore) bulls
Buffalo meat is still considered exotic in Brazil, and ~90% of it is marketed as cattle meat. The present study compared qualitative characteristics of the longissimus muscle from buffalo and cattle. Buffalo carcasses provide a higher yield of round cuts. Meat from buffalo carcasses had similar or better properties than that from cattle carcasses, and is a rich source of some hypocholesterolemic fatty acids, which help prevent cardiovascular diseases.
AN16628Effects of high concentrations of crude glycerin in diets for feedlot lambs: feeding behaviour, growth performance, carcass and non-carcass traits
Glycerin is the main by-product of the biodiesel industry and it is considered an attractive source of energy in livestock diets. Variations in corn prices make studies like the present one even more relevant. Total corn replacement could be possible depending on glycerin market price, as high inclusions (30%) reflect in greater number of days on feed. The addition of 10% of crude glycerin in diets for crossbred finishing lambs seems to be the most interesting strategy as it promotes greatest performance.
Eight Australian robotic milking farms were monitored to understand current and potential system performance. Despite a wide range in farm performance, the actual milkings, cows, milk yield and milking time could potentially be increased by a maximum of ~60%. Given the high cost of the equipment, if this potential maximum was achieved, the technology could become more attractive to dairy farmers and could increase the viability of existing installations.
AN16476Partitioning of energy and nitrogen in lactating primiparous and multiparous Holstein–Friesian cows with divergent residual feed intake
The efficiency of dietary energy and nitrogen use by cows is a high priority for dairy industries. The partitioning of energy and nitrogen in cows selected for high or low efficiency was highly variable. The results of these experiments suggested that selection for efficiency in growing dairy heifers may lead to a greater proportion of the diet being partitioned to milk and less to the waste products of heat energy and nitrogen excretion.
AN16470Effect of sunflower oil supplementation on methane emissions of dairy cows grazing Urochloa brizantha cv. marandu
The global livestock sector contributes a significant share to anthropogenic greenhouse gas emissions. The aim of this study was to examine the effects of supplementing sunflower oil on methane (CH4) emissions from lactating cows grazing tropical pasture. Methane emissions decreased about 20% when cows were supplemented with sunflower oil. This demonstrates potential for mitigating CH4 emissions without negatively affecting cow milk yield or composition. To be effective, mitigation actions need to be global.
AN13533Maternal body composition in seedstock herds. 2. Relationships between cow body composition and BREEDPLAN EBVs for Angus and Hereford cows
Relationships between BREEDPLAN estimated breeding values (EBVs) for 600-day weight, fat depth at P8 site (Rump), 12/13th rib fat depth (Rib), eye muscle area (EMA), and intramuscular fat (IMF) with body composition measures in first- and second-parity Angus and Hereford cows were investigated. BREEDPLAN EBVs for Rump, Rib, EMA and IMF were closely related to the equivalent ultrasound measure in Angus and Hereford cows at pre-calving and weaning. These results indicate that current BREEDPLAN carcass EBVs are associated with cow body composition, so if producers want to change the body composition of their cows, they can do so using existing BREEDPLAN carcass EBVs, and there appears no requirement for additional EBVs to describe cow body-composition traits for subcutaneous fat, EMA and IMF
AN14577Maternal body composition in seedstock herds. 5. Individual-trait selection direction aligns with breeder perspectives on maternal productivity
Variation in selection direction and genetic merit for Angus seedstock herds that contributed the majority of the data to the industry herd component of the Beef CRC Maternal Productivity Project was in investigated. The main differences in genetic merit among herds were associated with rib fat and rump fat EBVs, but there were also differences in for weight traits. This outcome was consistent with prior qualitative research. Despite differences in genetic merit among herds being generally small, they will manifest themselves in different productivity outcomes depending on the management system.
While mastitis in dairy cows is costly, affects the quality of milk and reduces milk production, internal teat sealants are used in mature dairy cows to mitigate these effects. Previous studies show internal teat sealant (ITS) use reduces mastitis in heifers; in addition to this effect, we saw an association between using ITS and improved milk production. Due to the study design we cannot provide assertion that the changes were a direct result of the ITS treatment; however, there is enough evidence to warrant further investigation in a prospective, controlled study.
AN16038Turning knowledge into practical benefit: a producer case-study increasing the return on investment in science
Efficiency of pasture use by beef cattle enterprises in southern Australia is traditionally ~35% because of a low adoption of existing knowledge and perceived risks from intensification. Principles from a risk-control system aimed at enhancing adoption were incorporated into a simple simulation model and applied to an enterprise on the central tablelands of New South Wales. Alternative management scenarios to optimise productivity and maximise profitability were evaluated and showed that interacting factors within an enterprise are too complex to effectively identify best strategies without the use of a system to integrate knowledge.
AN16291The use of certain medicinal plant extracts reduced in vitro methane production while improving in vitro organic matter digestibility
Reduction of enetric methane production from ruminant animals through the use of natural plant products is important because it causes global warming and energy loss to animals. Medicinal plant extracts, when tested on feed in the laboratory, reduced both enetric methane produced and energy loss by increasing feed digestibility. These plants can be used as replacements for artificial growth promoters in the meat and dairy industries to prevent antibiotic resistance syndrome in humans consuming animal products and animals can achieve faster maturity weight with lower methane emissions.
AN16058Effect of incorporating fungal-media residue in bedding on domestic-pig growth performance and welfare in winter
Adjusting the porosity of beddings can improve their ability to produce heat. The type of fungal-residue media has no effect on the growth performance of pigs. Smaller bedding granules may lead to pig cough. Fungal-residue bedding can partly replace sawdust in bedding. Bedding added 45% fungal residue can improve the welfare of pigs during winter.
AN16689The effect of cow-level factors on colostrum quality, passive immunity and health of neonatal calves in a pasture-based dairy operation
Pasture-based dairy operations allow for natural grazing behaviour; however, suboptimal nutrition may be more difficult to prevent due to variable quality of natural forages. The present study aimed to evaluate the effects of pregnant-cow management on colostrum quality, dairy calf health and growth. Cow weight loss during the dry period, an indicator of suboptimal nutrition, had a negative impact on colostrum quality but did not directly affect calf health and growth.
AN16496Dry matter intake and feeding behaviour of grazing dairy cows offered a mixed ration with or without canola meal
The inclusion of canola meal in a ration was investigated to determine its effect on intake and feeding behaviour. Experimental results indicated that the inclusion of canola meal in a ration increased pasture and total eating time, but there was no effect on pasture intake, as pasture allowance was low. The present research has implications for future investigations into the use of protein supplements in mixed ration feeding systems.
Hot weather negatively impacts on the well-being and performance of dairy cows. To address this, cooling infrastructure can be provided to the cows, where the present study found that access to shade pre-milking on a pasture-based automatic milking system was linked with increases in milk production and cow comfort. These findings will allow farmers to improve the production and well-being of their cows (without requiring additional labour), thereby improving the profitability of their farms.
The assignment of maternal parentage, although time-consuming and expensive using traditional methods, is essential for genetic improvement. The temporal frequency that cows and calves walk to water was measured to determine whether maternal pairs could be remotely identified and resulted in greater than 90% of calves being correctly assigned. This has the potential to greatly increase maternal parentage recording within extensive beef herds, therefore identifying superior genetics and resulting in more profitable beef enterprises.
AN16384Mapping of genome-wide copy number variations in the Iranian indigenous cattle using a dense SNP data set
Copy number variations (CNVs) have been known as one of the most important sources of variation in animal genome. In this study, a total of 957 CNVs was detected across autosomal genome of Iranian indigenous cattle using high-density single nucleotide polymorphism genotyping data. Results of this study provide a base for further investigation on genetic markers affecting the important production traits in Iranian indigenous cattle.
AN16014Influence of different inclusion levels and chain length of inulin on microbial ecology and the state of mucosal protective barrier in the large intestine of young pigs
The large intestine is a part of the gastrointestinal tract of pigs that is the most colonised by bacteria and its proper function is crucial for the maintenance of animal welfare and performance. Activity and composition of bacterial flora may be changed by feed additives such as inulin. Our results indicate that inulin, regardless of dietary level and degree of polymerisation, does not stimulate beneficial bacteria and immune system of the large intestine of young pigs.
AN15765Protection of α-amylase from proteolysis by adsorption to feed components in vitro and in the porcine small intestine
Digestion of feed nutrients in the small intestine of, for example, pigs involves enzymes specific for their substrate, for example, protein or starch, but these reactions take place in the presence of all other feed components. The effects of diet components on the activity of digestive enzymes was studied, and it was found that binding of enzymes to non-substrate feed components is both rapid and highly effective in stabilising enzymes against degradation. These results mean that studies of factors that control the rate of digestion of specific feed nutrient substrates need to take into account the possibility of interactions with non-substrate feed components.
Dairy cows with several calvings would have a healthier milk fat than would cows in their first calving. The present study was conducted to investigate the effects of parity on the fatty acid profile in milk fat from dairy cows with different grazing times. Although the milk from primiparous cows had a lower fat content, it had a higher grade of unsaturation than did milk from multiparous cows, so their milk could be considered as healthier milk.
AN16333The effect of the dietary protein restriction and re-feeding on the content of leptin, IGF-I and urea nitrogen in the blood plasma and growth performance in pigs
Dietary restriction result in accelerated body growth in pigs during re-feeding, but it is not clear whether this phenomenon is due to changes in metabolic hormones, lipid deposition or protein metabolism. Effect of dietary protein restriction on the body growth and blood content of some metabolic hormones as markers of lipid or protein metabolism was studied. During the re-feeding, increased daily weight gains and concentrations of plasma leptin and urea nitrogen were observed, indicating greater lipid deposition and protein breakdown.
AN16157Early mother–young relationship and feeding behaviour of lambs are unaffected by low pasture allowance until the beginning of the last third of gestation in single-bearing ewes
In extensive production systems, native pasture availability decreases in winter, thus, ewes are undernourished during gestation. We subjected pregnant ewes to two different levels of pasture allowances, both followed by an increase in nutrient supply during the last third of gestation. Ewe-lamb behaviours at birth, lambs’ growth and feeding behaviours during rearing were unaffected by the level of pasture allowance.
This study examined risk factors for dystocia, which is a major cause of lamb deaths. Dystocia increased with ewe age and for low birthweights was associated with increased litter size. Low birthweight dystocia may be a different condition from dystocia with high birthweight.
AN16258Methionine supplementation of low-protein diet and subsequent feeding of low-energy diet on the performance and blood chemical profile of broiler chickens
To improve productive performance, the findings of this study should be useful for the feed and broiler chicken industry. The present study was conducted to investigate the effect of reducing dietary protein with methionine supplementation and subsequent feeding of a low-energy diet on growth performance of broiler chickens. The results indicate that growth performance and carcass quality were significantly improved by this method, which may be an appropriated tool for improving production of broiler chickens.
AN16471Individualised feeding of concentrate supplement in pasture-based dairy systems: practices and perceptions of New Zealand dairy farmers and their advisors
The use of individualised feeding has increased within New Zealand dairy-farm systems in the past decade; however, little information exists on farmer motivations, practices, perceptions and challenges. A survey and interviews were conducted with farmers and farm consultants throughout New Zealand to explore these themes. Farmers using individualised feeding systems strongly believed that there was value from this investment, particularly in feeding individual cows or mobs within a herd with minimal additional effort, but evidence of profitability was lacking and there was insufficient information available on optimum feeding strategies.
AN16319Fatty acid profile, oxidative stability and sensory quality of breast meat from turkeys fed diets with graded levels of flaxseed oil for different periods of time
A very high n-6 : n-3 ratio, as is found in today’s Western diets, promotes the pathogenesis of many diseases in consumers. The results of our study indicate that the recommended n-6 : n-3 polyunsaturated fatty acid ratio in turkey breast meat may be easily reached if birds are fed 2.5% flaxseed oil for the last 3 weeks before slaughter. Therefore, such a feeding program with a relatively low application of dietary flaxseed oil could be considered a suitable delivery vehicle for health-promoting fatty acids.
For science to be effectively valorised in practise, stakeholders should be part of the research process. In this study, a management problem in pig production was analysed with stakeholders, which led to guidelines on how to perform such a process. These guidelines can well be considered in any research effort aiming at practical implementation of its results.
AN15864Associative effects between Arachis pintoi and dwarf elephantgrass hays on nutritional value in sheep
The inclusion of forage legumes in ruminant production systems presents nutritional, economic and environmental benefits. The aim of the present study was to evaluate the effect of different levels of inclusion of peanut hay on the nutritional value of diets based on dwarf elephantgrass hay. It was found that including peanut hay at up to 330 g/kg of dry matter in dwarf elephantgrass-based diets is sufficient to maximise the digestible-OM intake.
AN16303Feed efficiency and enteric methane production of Nellore cattle in the feedlot and on pasture
Residual feed intake has been recommended as a selection criterion for beef cattle to increase individual feed efficiency. Efficient or low residual feed-intake cattle have a significant economic advantage since they consume less feed than expected for their weight and rate of gain compared with their more inefficient or high residual feed-intake counterparts. The results do not support the hypothesis that an increase in feed efficiency, evaluated in growing animals in feedlot-performance tests, decreases enteric CH4 production.
Diversifying farm activities can reduce the risk of agricultural production. Diversifying the type and proportion of pasture species grown was explored as a risk management option for dairying, and showed that there may be benefits of increased pasture growth rates at critical times of the production year, but the variability of the growth rate was not reduced.
AN16420Phosphorus supplementation with or without other minerals, ionophore and antibiotic did not affect performance of Nellore bulls receiving high-grain diets, but increased phosphorus excretion and dietary costs
Phosphorus has nutritional, environmental and economic importance due to its high cost and potential for soil and water contamination. We evaluated the effect of phosphorus supplementation, with or without other minerals, ionophore and antibiotic, on animal performance, feeding costs and phosphorus utilisation in Nellore bulls finished in a feedlot. Minerals, ionophore and antibiotic were not necessary to ensure health and performance of feedlot Nellore bulls, with emphasis for the reduction of pollution and feeding costs in Brazilians feedlots.
AN16465Using a ‘network of practice’ approach to match grazing decision-support system design with farmer practice
The use of pasture measurement tools and decision-support systems for grazing management remains limited on New Zealand dairy farms. Perspectives of farmers, rural professionals, farming-system specialists and software developers were analysed to understand how decision support-tool design could be matched with farmer practice. The research highlighted a need for flexible tools incorporating differences in user goals, decision making, mobility and desired outputs. Key attributes identified were seasonality, simplicity, ability to trial before purchase, flexibility in application and scalability to match farm systems.
AN16522Sex and breed affect plasma glucose, lactate, cortisol, meat quality but not muscle glycolytic potential of Dorper and Merino lambs
When animals are exposed to a high level of stress, the animal’s body undergoes physiological changes as a means of maintaining homeostasis, thus negatively affecting the quality of meat produced. This study investigated breed and sex differences in response to pre-slaughter stress and the effects on stress indicators in the blood, muscle and overall meat quality attributes. The ewes and Dorper breed perceived the slaughter process to be more stressful compared with rams and the Merino breed.
AN16307Development of mathematical models to predict calcium, magnesium and selenium excretion from lactating Holstein cows
Cows are often overfed calcium, magnesium and selenium, leading to these minerals’ excretion into the environment and, subsequently, negative health effects for the cows and environment. This study was successful in its aim of developing equations to predict excretion levels of these minerals. Agricultural industry members could use the equations to reduce mineral excretion levels while ensuring cows still receive a sufficient amount.
AN16419Growing goats of different sexes have distinct metabolic responses to continuous feed restriction
One of the main nutritional challenges imposed on animals is feed restriction; however, it is still unknown how goats of different sexes react physiologically to the continuous restriction of nutrients. This study investigated the effect of sex on metabolic changes in growing goats subjected to levels of feed restriction. Our results show that under feed restriction, females and males react differently physiologically and are able to use different metabolic responses to meet their energy and protein demands.
AN16492Assessing the reliability of dynamical and historical climate forecasts in simulating hindcast pasture growth rates
A priori knowledge of seasonal pasture growth rates helps livestock farmers estimate likely pasture availability and thus plan their feed budget. We compared pasture growth rates generated using climate forecasts derived from either historical archives or from the global circulation model POAMA. Hindcast growth rates (retrospective forecasts) were simulated using posterior weather data and were used as a surrogate for actual growth rates. We found that (1) statistical methods of comparing forecast data with hindcast or measured data are important, particularly if the comparison is made between a distribution of points and a single value, (2) 1-month growth-rate forecasts have less uncertainty than forecast durations of 2 or 3 months, and (3) there is little difference between growth rates simulated using climate data from either historical records or from global circulation models.
Increasing ruminal input of buffers from the diet or saliva yields bases or buffers such as ammonia could prevent a depression in ruminal pH. Supplementation of banana flower powder either with or without urea could enhance rumen ecology and fermentation efficiency. Therefore, banana flower powder is potentially used as a rumen buffer agent for high-producing dairy cattle promising to replace sodium bicarbonate.
AN16289Dose-dependent effects of probiotic supplementation on bone characteristics and mineralisation in meat-type female turkeys
Bacterial population could influence bone development through the bone–gut axis. The properties of long bones in female turkeys are affected through probiotic-supplemented diets in a dose-dependent manner. It seems that the administration of the probiotic at a higher concentration of cells is more beneficial for bone development in turkeys.
Animal performance and behavioural responses were evaluated under different production systems, throughout two seasons. Time of the day and especially the seasons influenced behavioural responses and animal performance. Meat production can be increased when the system includes rotation with crops (soybean and maize). Silvopastoral systems provide Nellore steers with a more comfortable and preferred environment for idleness and rumination.
AN16376Bone mineral density in the tail-bones of cattle: effect of dietary phosphorus status, liveweight, age and physiological status
Phosphorus deficiency in cattle grazing rangelands may have severe adverse effects. Single photon absorptiometry was used in on-farm experiments to measure tail-bone mineral density and thus diagnose bone phosphorus. Prolonged phosphorus deficiency markedly reduced mineral density of tail-bone in young-growing and reproducing cattle, but not in mature cows. Single photon absorptiometry may be valuable to diagnose long-term phosphorus deficiency in cattle.
AN13258Maternal body composition in seedstock herds. 4. Genetic parameters for body composition of Angus and Hereford cows
Australian beef producers have been successful in achieving significant genetic gains in body composition traits. This study examined the genetics of body composition traits of cows at pre-calving and weaning in their first and second parities. The results of this study indicate that genetic improvement in body composition traits in cows is possible, and that body composition information recorded at yearling age is a reasonably good predictor of later in life performance for these traits.
Mature dairy cows with good conformation are profitable to the dairy enterprise through their increased stay in production. An evaluation of the extent to which conformation components influence longevity in South African dairy cows showed a significant influence of traits related to udder suspension. Cows with pendulous udders were highly predisposed to culling leading to reduced longevity and productivity both of which will ultimately reduce the profitability of the enterprise.
AN16268Relationship between the fatty acid composition of uropygial gland secretion and blood of meat chickens receiving different dietary fats
Determining the fatty acid status of chickens requires invasive methods to obtain blood samples for analysis. We postulated that measuring the fatty acid composition of preen oil, which is externally secreted from the uropygial gland of live chickens could be an alternative non-invasive method. However, the results showed that the fatty composition of preen oil is not a suitable indicator of the whole blood fatty acid profile in chickens.
AN13060Maternal body composition in seedstock herds. 1. Grazing management strategy influences perspectives on optimal balance of production traits and maternal productivity
Seedstock breeders’ perspectives on maternal productivity in beef cattle were investigated through the use of qualitative in-depth semi-structured interviews. Divergence in breeders’ attitudes to cow management and body condition fluctuation were evident and this was associated with differing selection emphasis for production traits compared with perceived resilience traits. The results demonstrated that among seedstock breeders targeting similar end markets, substantial variation in animal selection and management exists that requires further characterisation to ensure breeding programs and animal management are optimal.
The profitability of a dairy business in northern Victoria from 2003–2004 to 2014–2015 was compared with the performance of other dairy and non-agricultural investments. The analysis showed the farm performed well relative to other dairy businesses in Victoria, and alternative investments, such as shares, bonds and property. Compound annual return to capital over the 12 years was 12.4% (real), with over half the return from the farming operation and the remainder from owning assets that appreciated in value.
AN16463A farm-scale framework to assess potential farm- and regional-scale implications of removing palm-kernel expeller as a supplementary feed for dairy cows
Growing consumer awareness and the expected expansion of the Asian dairy sector may increase pressure to find alternatives to palm-kernel expeller (PKE) as a supplementary feed for dairy cows in New Zealand. We examined the possibilities of domestically grown barley as a PKE replacement in Southland. The farm-scale framework was capable of exploring some of the farm and regional production, economic and environmental implications from such replacement.
AN16449A practical future-scenarios selection tool to breed for heat tolerance in Australian dairy cattle
Selection for heat-tolerant dairy cattle has become important, especially in the global warming context. We developed a tool that enables farmers to make selection decisions of animals that leads to improvements in heat tolerance and profitability simultaneously. The use of the tool will contribute to improving milk production and welfare of animals, especially in warm regions.
Nutrient losses to the environment can be caused by dairy cows grazing crops over the winter period. The aim of the study was to document the prevailing wintering practices in the Canterbury region, with results indicating a reliance on kale and fodder beet located off the dairy farm. This information could be used to identify opportunities for reducing nutrient losses and as a base for evaluating practice change in the future.
AN16233Potato processing waste in beef finishing diets; effects on performance, carcass and meat quality
Waste streams from potato processing represent a high-value feedstuff for ruminants but are underutilised in many parts of the world. This study showed that potato processing waste can be fed to beef cattle at 80% of the diet dry matter without affecting animal productivity or meat quality. Where locally available, potato processing waste represents a low-cost, high-quality feed source for beef-finishing operations.
Twenty young Cika and 20 Simmental bulls were finished post-weaning on two diets and slaughtered at similar carcass weights. Cika bulls produced carcasses with a higher dressing percentage, more fat and less tendons and bones. The Longissimus thoracis muscle of Cika bulls had a lower pH, higher redness, yellowness and drip loss, and a more intense flavour.
AN15739Effect of quantity and source of rumen nitrogen on the efficiency of microbial protein synthesis in steers consuming tropical forage
Increases in the efficiency of microbial protein synthesis (EMPS) of cattle grazing tropical pastures should lead to increased liveweight gain through increased total metabolisable protein supply. Rumen degradable protein (RDP) supply from tropical pastures is low; hence, increasing the dietary supply of RDP is a strategy to increase EMPS. Our study showed that only high amounts of RDP supply to the rumen, in the form of true protein, resulting in increased EMPS. However, at lower intakes of RDP, which were formulated to achieve EMPS in the range suggested in the feedings standards, there was no difference in supplying the RDP as non-protein nitrogen or degradable true protein.
AN15131Polymorphisms of kappa-casein gene and their effects on milk production traits in Holstein, Jersey and Brown Swiss cattle*
κ-CN plays a critical role in the formation and stabilisation of casein micelles, and influences the manufacturing properties of milk. Although genotypes for κ-CN polymorphisms were associated with protein and solids-not-fat content of milk in Hostein and Brown Swiss, they had an effect on fat content of milk in Jersey. B allele was associated with increasing milk quality, therefore, selection of B allele could provide economic advantage for increasing milk quality.
AN14851Performance and metabolism of dairy calves fed starter feed containing citrus pulp as a replacement for corn
Dairy calves may benefit from feeding citrus pulp (CSP) as a replacement for corn, considering the possibility of ruminal acidosis and the high grain costs. The study aimed to evaluate the effect of replacing corn grain with CSP in the starter concentrate on performance and metabolism of dairy calves. The partial or total replacement of corn by CSP in the starter feed of dairy calves did not affect performance and contributed to the better rumen development.
AN15845Contract bonus systems to encourage biosecurity adoption on small-scale broiler farms in Indonesia
Improved biosecurity in smallholder broiler farms in Indonesia has the potential to reduce disease and improve livelihoods. There are a range of contracts available to smallholders which provide different incentive structures to invest in biosecurity. An analysis of six smallholder-company contracts and how they are able to reward farmers who are approved to market their product as ‘Healthy Farm’ chickens indicates that smallholders need to be selective in their choice of partner company as only three of the six contract types adequately reward smallholders who are investing in farm biosecurity.
AN15146Effects of the citrus flavonoid extract Bioflavex or its pure components on rumen fermentation of intensively reared beef steers
The use of plant secondary compounds (i.e. flavonoids) to enhance ruminal fermentation condition has become the mainstream of rumen studies. Our study shows the effectiveness of Bioflavex supplementation in steers for preventing a collapse in pH and modifying the activity of lactate-consuming bacteria. Its optimum effect would be expected in short administration (feedlot) period due to adaptation of rumen environment to the presence of Bioflavex.
AN14950Effects of Saccharomyces cerevisiae and rumen bypass-fat supplementation on growth, nutrient utilisation, rumen fermentation and carcass traits of lambs
Productivity in lambs can be enhanced by strategic supplementation with energy- and protein-rich feedstuffs. Feeding of lambs on higher levels of concentrate leads to lower rumen pH and sometimes rumen acidosis, which disturbs the balance of rumen and intestinal microflora. Inclusion of rumen bypass fat at lower levels yielded better gains; however, at higher levels it affected fibre digestibility due to adverse effects on microbial growth. Microbial cultures (probiotics) are being tried as natural feed additives for maintaining microbial balance in the gastro-intestinal tract and, thereby, overall animal production. Present study envisaged the use of live culture of Saccharomyces cerevisiae to Malpura lambs fed ad libitum concentrate with and without rumen bypass fat.
AN15501Comparison of ruminal fermentation parameters, fatty acid composition and flavour of beef in finishing bulls fed active dry yeast (Saccharomyces cerevisiae) and yeast culture
What is effect of yeast preparations on fatty acids and flavour which are closely related to beef quality? A research was conducted, of which results indicated that yeast products had little effect on individual fatty acid but improved the tenderness of beef. The findings will be beneficial in regulating beef quality by yeast preparations in the near future.
AN16256Intake of milk and pasture and growth rate of calves reared by cows with high or low potential for milk production
Rapid pre- and post-weaning growth rates of calves are important for efficient beef production. This experiment demonstrated that although calves with high growth potential partially compensated for the low milk intake by increasing their pasture intake, liveweight advantages from increased milk intake persisted to one year of age. High-yielding beef-cross-dairy cows can increase liveweight of calves.
AN16100Effects of partially replacing barley with sugar beet pulp, with and without roasted canola seeds, on performance, rumen histology and fermentation patterns in finishing Arabian lambs
A high-concentrate diet commonly causes digestive disorders in finishing lambs. This study aimed to evaluate effects of sugar beet pulp and canola seeds on ruminal fermentation and morphology of finishing lambs. Partial use of sugar beet pulp and roasted canola seed inclusion successfully optimized ruminal environment and had beneficial effects on morphology of the rumen in lambs fed a high-concentrate diet.
Bos indicus cattle are often castrated after six months of age without pain relief. Measures of pain that include pedometry, blood cortisol concentrations, and baulk and crush scores were used to characterise post-surgical castration pain and determine whether perioperative lignocaine or meloxicam or both reduced pain. Pedometer measures and cortisol concentrations proved useful and showed that strategic use of analgesics is viable in extensive farming situations and provides benefit to animals undergoing castration.
AN16529Effect of replacing a commercial pelleted calf meal with lucerne leaf-meal on performance of neonatal and transitional Holstein heifer calves
The low fibre, high β-carotene and protein contents in lucerne leaf-meal (LLM) make it an attractive substitute forage for commercial calf feeding. The present study assessed the performance of pre-weaned Holstein heifers supplemented with LLM. Holstein heifer calves with forage provision (LLM) had higher nutrient intake and greater growth performance than the control diet. These results confirm the role of LLM in improving dairy calf’s performance.
AN16394Accumulation and depletion of indospicine in calves (Bos taurus) fed creeping indigo (Indigofera spicata)
The natural toxin indospicine accumulates in meat of animals grazing Indigofera pasture plants, and has been responsible for secondary poisoning of dogs fed indospicine-contaminated horsemeat and camel meat. The present research highlights the similar accumulation of indospicine residues in calves fed a diet containing Indigofera spicata (creeping indigo). Indospicine has been established as causing both reproductive losses and liver disease, and likely contributes to cattle productivity losses in areas where Indigofera species (such as Birdsville indigo) are prevalent.
AN16111Fatty acid profile of ghee derived from two genotypes (cattle–yak vs yak) grazing different alpine Himalayan pasture sites
Fatty acid profile of ghee obtained from cattle × yak hybrids during a transhumant movement cycle between 2600 and 4500 m a.s.l. was influenced by pasture site. The hypothesis that yak ghee contains, in general, higher proportions of functional FAs than does ghee from cattle × yak hybrids (cattle × yak) could not be verified. However, yak ghee contained higher proportions of long-chain n-3 polyunsaturated fatty acids. More studies are needed to exclude possible factors of influence.
AN15440Increased genetic gains in multi-trait sheep indices using female reproductive technologies combined with optimal contribution selection and genomic breeding values
A study to use female reproductive technologies with genomic selection in sheep breeding programs was conducted to investigate how much extra genetic progress could be achieved over a 10-year period. Both genomic selection and reproductive technologies facilitated enhanced rates of genetic gain and displayed strong synergies. Genomic information collected early in life allowed for larger gains in traits that are measured after selection.
AN15348Effect of replacing palm fat with high-linoleic cold-pressed rapeseed or sunflower cakes on fatty acid biohydrogenation in an artificial rumen (Rusitec)
This study aimed to evaluate the response of ruminal metabolism of dietary fatty acids to replacing prilled palm fat, a saturated fat, with cold-pressed rapeseed cake or cold-pressed sunflower cakes, by-products of on-farm biodiesel manufacturing very rich in unsaturated fatty acids. Replacing palm fat with cold-pressed rapeseed cake or cold-pressed sunflower cakes decreased total saturated fatty acids and enhanced cis-monounsaturated fatty acids and vaccenic acid accumulation in rumen fat without shifting biohydrogenation pathways towards the formation of C18:1 trans-10.
AN15067Changes in carbohydrate and protein fractions during ensiling of alfalfa treated with previously fermented alfalfa juice or lactic acid bacteria inoculants
Without the addition of inoculants, alfalfa silages often result in deleterious changes to the nutritive value. This study investigated the effects of previously fermented juice (PFJ) and lactic acid bacteria (LAB) inoculants and suggested effect of PFJ may be comparable to, or even better than, that of LAB inoculants. Adding PFJ to improve alfalfa silage quality is a cost-effective way.
AN15642Verification of micrometeorologically determined nitrous oxide fluxes following controlled release from pasture
Emissions of the greenhouse gas nitrous oxide arise following deposition of excretal nitrogen from cattle grazing on pasture. Accurate measurement is challenging because the emissions can be very variable in time and space; paddock-scale methods can capture and integrate through this variability. We present here the first experiment to independently verify a paddock-scale emission method with a known emission of nitrous oxide. We show that emission is likely to be under-estimated using uncorrected vertical concentration-difference measurements.
AN16180Productivity and profitability of forage options for beef production in the subtropics of northern Australia
Targeted use of high quality forages is an intensification strategy that has the potential to improve the profitability of northern beef businesses through increasing enterprise turnover and productivity. Our study provided comparative data for forage, animal and economic performance for a range of forage options for dryland beef production in northern Australia. The data indicated that perennial legume-grass pastures, and particularly leucaena-grass, resulted in greater profitability than annual forage crops or perennial grass and that this was primarily due to the relatively low forage costs for perennial legume-grass pastures (compared with annual forage crops) combined with their high productivity.
AN16186Bayesian estimates of genetic relationship between calving difficulty and productive and reproductive performance in Holstein cows
In recent years, dairy cattle breeders have shown an increasing interest in selection for functional traits such as calving difficulty. The aim of the present study was to estimate genetic correlation between calving difficulty and productive and reproductive performance of Holstein cows. Exploitable genetic variation in calving difficulty, productive and reproductive traits could be applied in designing future genetic selection plans for Iranian Holsteins.
AN16002Nitrate supplementation has marginal effects on enteric methane production from Bos indicus steers fed Flinders grass (Iseilema spp.) hay, but elevates blood methaemoglobin concentrations
This experiment quantified the methane abatement potential of calcium nitrate for extensively managed beef cattle. Nitrates provide an alternative sink for H that would otherwise support methanogenesis. Elevated concentrations of methaemoglobin indicate that replacing urea with nitrate in supplements for use in the northern rangelands is inappropriate where supplement intake cannot be controlled and forage quality is seasonally variable.
AN16286Revised greenhouse-gas emissions from Australian dairy farms following application of updated methodology
The present study examined the effect of changes to the national inventory on the emission intensity of milk production of 41 Australian dairy farms previously assessed using the Dairy Greenhouse Gas Abatement Strategies calculator. The national mean emission intensity of milk production has increased, although individual farm emissions have either increased or decreased, depending on a range of factors. Methane from waste management has emerged a new ‘hot spot’, which will need consideration in terms of mitigation options moving forward.
The cryopreservation process compromises the sperm DNA integrity, and spermatozoa with a high level of damaged DNA might have low potential for fertilization. In this study the comet tail measures were used to assess the extent of DNA damage to frozen-thawed spermatozoa and detected marked inter-boar variability to cryo-induced sperm DNA damage. It can be suggested that the comet-assay parameters have the potential to be a powerful tool to improve the sperm evaluation of post-thaw semen quality.
AN16107Genetic parameters for fatty acids in intramuscular fat from feedlot-finished Nelore carcasses
Reports of genetic parameter estimates for fatty acid (FA) profile are scarce for zebu breeds, and it is important to known whether selection is feasible to decrease harmful FA and increase health beneficial FA. The aim of the present study was to estimate genetic parameters of beef FA composition of intramuscular fat in Nelore bulls. The results of this study should help seek strategies for genetic selection and/or genetic-based diet management to enhance the beef FA profile in zebu cattle.
AN16165Detection of candidate genes for growth and carcass traits using genome-wide association strategy in Chinese Simmental beef cattle
Detecting major genes, which control important economic traits in livestock, is meaningful to cattle breeding. We tried to explain the phenotype variance in genomic level, and explored the candidate genes for cattle growth and carcass traits using genome-wide association studies analysis. This study detected a total of 18 candidate genes and their harboured associated regions, which will facilitate mark-assist selection in Chinese Simmental cattle.
AN15645Enteric methane emissions, intake, and performance of young Nellore bulls fed different sources of forage in concentrate-rich diets containing crude glycerine
Finishing animals in feedlots with diets rich in concentrates can be a strategy to reduce enteric CH4 emissions; however can lead to ruminal upsets decreasing animal performance. This study evaluated the effect of different sources of forage in concentrate-rich diets on feed intake, performance, and enteric methane emissions. Forages of low quality may be used at 15% neutral detergent fibre from forage without compromising intake, performance, or enteric methane emissions.
There is a growing interest in equid milk production, involving some commercial and economic aspects. Knowledge about equids’ milk production and application of mathematical models on it are not well developed. This paper’s result indicates Wood’s model as a good mathematical model to describe and predict equid milk production. Moreover, normalised data according metabolic liveweight showed that IHDH mares produce more milk than Martina Franca donkeys.
AN15314Effect of feeding forage characteristic of wet- or dry-season tropical C4 grass in northern Australia, on methane production, intake and rumen outflow rates in Bos indicus steers
Given the importance of methane as a greenhouse gas, methane production was measured from tropical beef cattle consuming pastures typical of the northern Australian rangelands during the seasonal changes in diet quality. The work aimed to quantify methane produced from diets typical of the rangelands and compare against equations commonly used to estimate methane production from cattle. Methane produced on a daily basis was affected by diet quality and is likely overestimated in Australian cattle consuming low quality forage.
AN16322Utilisation of giant taro (Alocasia macrorrhiza) root meal with or without coconut oil slurry by layers and broilers
The effects of feeding giant taro root meal with or without coconut oil slurry on the performance of layers and broilers were investigated. Replacement of dietary maize at a level greater than 10% of the meal depressed performance of both egg- and meat-type birds. Supplementation with coconut oil slurry allowed utilisation of 20% of the meal by laying hens, but had no effect in young broiler chickens.
Improving smallholder cattle feeding practices in Cambodia is necessary to reduce labour demands and improve income from cattle raising. The present study investigated the socioeconomic impacts of forage technology adoption with results showing significant time savings for forage growing households and reduced involvement of women and children. Forage technology should therefore be recommended to cattle-owning households as an alternative to traditional feeding practices to save time, increase income and improve livelihoods.
The factors affecting the fatty acid profile of meat and those that are related with its quality, should be determined in a mixture of the major muscles, since humans consume different parts of the carcass. The fatty acid composition of muscles reflects that of the milk source (maternal or artificial) but the response of each muscle was not the same for all the fatty acids. Lower slaughtered age may provide a more beneficial fatty acid profile, from a human health point of view.
As part of the national beef cattle genetic evaluation in Australia 50 935 Angus and 50 930 Limousin calves were scored for docility. Genetic parameters for docility score were estimated using a threshold animal model from a Bayesian analysis. The heritability of docility score was estimated as 0.21 and 0.39 in Angus and Limousin, respectively. Weak but favourable genetic correlations between docility score and production traits indicate that selection to improve temperament can occur without having an adverse effect on growth, fat, muscle and reproduction.
Pre-slaughter process is considered a high risk of animal stress, which can cause carcasses bruising that represent significant losses for the meat industry. Our results indicated that specific conditions of sex, loading facilities, cattle handling, transport time, hauling-truck types, truck animal-load density and unloading time influenced the occurrence of bruises. Thus, special handling practices and personnel training measures should be undertaken to mitigate losses pre-slaughter.
AN16138Priming anoestrous Corriedale ewes with progesterone and gonadotrophin-releasing hormone causes cervical tissue remodelling due to metalloproteinase-2 (MMP-2) activity
This paper provides evidence of collagen remodelling in the cervix of anoestrous ewes induced to ovulate with progesterone and GnRH. The activity of MMP-2 collagenase (but not of MMP-9) was higher on Day 1 after the induced ovulation than on Day 5, inversely to the collagen concentration, demonstrating that activation of MMP-2 is a key factor of cervical collagen remodelling in anoestrous ewes around induced ovulation.
AN15839Effects of time of initiation of feeding after hatching and diet composition on performance, carcass characteristics, digestive tract development and immune responses of broilers
Delayed feeding after hatching adversely affects the rate of growth as well as gastrointestinal and immunological development. In this study, the effects of time of initiation of feeding after hatching and diet composition were evaluated in broiler chickens. Feeding a maize-soybean meal starter diet immediately after hatch had a beneficial effect on growth performance and immune response of broilers and improved intestinal morphology.
AN15719Effect of weaning age and milk feeding level on pre- and post-weaning growth performance of Sahiwal calves
Pre-weaning feeding cost may be reduced by early weaning of calves, offering solid feeds at an early age, or using milk replacers. In this study, early or late-weaning coupled with low- and high-milk combinations were tested to see growth performance of Sahiwal calves. It was concluded that offering milk at 15% of bodyweight and weaning at 8 weeks was a low-cost feeding strategy.
The quality of three muscles from farmed fallow deer (Dama dama) was analysed in the study so as to compare the functionality of these muscles after storage in vacuum packaging. The results indicated a different technological quality of the analysed muscles, and thus a need to further explore the background of these differences as well as the factors affecting the maturation of deer meat during chilled storage.
AN16226The impacts of dietary Nigella sativa meal and Avizyme on growth, nutrient digestibility and blood metabolites of meat-type quail
The continuous increase in prices of traditional feedstuffs like corn and soybean meal made a dire need for low-cost, untraditional and balanced diets. Nigella sativa meal was included in quail diets as untraditional feedstuff to reduce costs and to examine its impacts on productive and health aspects. Great results were obtained by the inclusion of 15% Nigella sativa meal in growing quails diets, which positively supported growth and feed utilisation.
The marine alga Asparagopsis taxiformis has been shown to inhibit methane production in vitro. The present study compared the methane production from sheep offered increasing inclusion levels of Asparagopsis for 72 days. We found that a high-fibre pelleted diet supplemented with Asparagopsis resulted in up to 80% reduction in methane output compared with the same diet without Asparagopsis.
The pasture yield benefits available from including white clover in mixtures with perennial ryegrass are often overlooked. Ryegrass monocultures were compared with mixtures in experiments across multiple environments and managements in New Zealand, revealing a mean yield advantage of 2.3 t DM/ha per year to mixtures. Management strategies to sustain a threshold of 20–30% clover in mixtures are described.
AN15804Differences between sexes, muscles and aging times on the quality of meat from Wagyu × Angus cattle finished in feedlot
We assessed the characteristics and aging time of meat from Wagyu × Angus animals of both sexes. Females had the best marbling score, greater fat content, and less shear force. Crossbreeding with Wagyu and Angus is interesting to produce high-quality beef. Meat aging reduced shear force and increased ultimate pH of the longissimus thoracis. We conclude that aging for 7 days is already sufficient to produce an acceptably tender meat based on shear force values.
The identification of critical points during transport and slaughtering procedures may significantly improve animal welfare during transport. In heavy pigs, long travel duration, low stocking density and overnight lairage resulted in increased animal losses. The routine collection and analysis of animal-loss data at slaughterhouses could reduce the economic impact of animal losses and be of help in improving future legislation on the protection of pigs during transport.
Vitamin B6 has been associated with protein metabolism. However, the effects of dietary vitamin B6 on the skeletal muscle protein metabolism of growing rabbits are unknown. Our results indicate that the addition of dietary vitamin B6 can increase the skeletal muscle protein synthesis of growing rabbits, and it can be used to improve meat performance of domestic animals in the future.
AN15738Genetic and phenotypic parameters for reproduction, production and bodyweight traits in Australian fine-wool Merino sheep
Reproductive performance is one of the main profit drivers of the Merino sheep industries. With an increased emphasis on lifetime production and reproduction in Merino sheep, it is important to consider the genetic relationship between production and reproduction traits for yearling and adult expressions. The analysis and definition of life time reproduction traits require careful consideration and more work in this area is needed.
AN16265Effects of substituting corn with steam-flaked sorghum on growth, digestion and blood metabolites in young cattle fed feedlot diets
The research about sorghum and its processing as feed is necessary to to expand the application scope of sorghum. Partial substituting ground corn grain with steam-flaked sorghum grain in beef cattle diets could improve growth performance. The optimum substitution rate of ground corn grain with steam-flaked sorghum grain was 2/3 (DM basis).
AN16025Frequent handling of grazing beef cattle maintained under the rotational stocking method improves temperament over time
We assessed beef cattle temperament in the Brazilian Amazon region where the deforestation for cattle production is a cause of concern, and the intensification of beef cattle production using rotational grazing systems arises as an alternative. We found that the rotational stocking method improves cattle temperament over time, resulting in less reactive animals when compared with those kept in an alternate stocking method.
AN16175Effects of phytase, calcium source, calcium concentration and particle size on broiler performance, nutrient digestibility and skeletal integrity
High dietary calcium concentrations in poultry diets have a negative effect on bird performance, due mainly to a reduction in phytate-phosphorus digestibility. To counteract this, diets are supplemented with inorganic phosphorus and phytase. The ability to replace high dietary calcium concentrations with lower dietary calcium concentrations supplied by a highly soluble calcium source has the potential to alleviate the problems associated with high dietary calcium while maintaining optimal bird performance and skeletal health.
AN16028Effects of a single injection of Flunixin meglumine or Carprofen postpartum on haematological parameters, productive performance and fertility of dairy cattle
The administration of a NSAID at parturition should reduce the associated inflammation and pain associated with calving but the evidence of a clinical benefit of their use and the relative dosage in cows with puerperal disease is limited and equivocal. The aim of the study was to evaluate the effects of a single injection of Flunixin meglumine (FM; intramuscular) or Carprofen (CA; subcutaneous) within 12 h after calving on dairy cattle haematological parameters, dry matter intake, productive performance and fertility. The findings evidenced that a single injection of FM or CA to non-febrile cows immediately after parturition positively affects the metabolic adaptation of the cows at the onset of lactation and this aspect can positively influence reproductive performances and the culling rate.
Piglets weaned at 26 days of age have less post-weaning stress and higher feed intake, and therefore outweigh best during the critical period post-weaning. For this reason, the digestible tryptophan to lysine ratio for maximum performance is changed. This research determined the optimal digestible tryptophan to lysine ratios in piglets weaned at 26 days old is estimated at 0.22. Therefore, piglets weaned with at least 26 days develop better than piglets weaned early.
AN13218Divergent genotypes for fatness or residual feed intake in Angus cattle. 2. Body composition but not reproduction was affected in first-parity cows on both low and high levels of nutrition
This paper documents the impact of selection for reduced fatness and increased feed efficiency on nutritionally restricted, first-parity cows. The aim was to determine whether maternal productivity was compromised in these genotypes when energy input was restricted, with the result being that although body composition changed, there was no impact on reproductive traits. Producers can continue to select for reduced fatness and increased feed efficiency without compromising productivity of the female herd.
AN15636Divergent genotypes for fatness or residual feed intake in Angus cattle. 7. Low-fat and low-RFI cows produce more liveweight and better gross margins than do high-fat and high-RFI cows when managed under the same conditions
Economic evaluation of experiments conducted on 500 Angus cows to measure maternal productivity performance provides direction to the national industry. Cows with low fat or low RFI generated more income by selling more liveweight due to heavier weights and higher stocking rates and therefore were more profitable, even when accounting for differences in reproductive performance. This finding has potential to influence breeding objectives.
AN14874Modelling systems to describe maternal productivity, with the aim of improving beef production efficiency by eliciting practice change
Productivity of the cow has the largest effect on productivity of the beef industry particularly given the high cost of feeding cows. Recent research has demonstrated that cow productivity is impacted by (1) heifer development before puberty, (2) the effects the relationship between cow feed requirements and nutrient availability have on reproductive success, and (3) the changes in the cow herd that are a result of breeding decisions. Decision support systems based on computer simulation models can be developed to address these issues by providing outputs that help producers during their on-farm decision-making.
AN14797Divergent breeding values for fatness or residual feed intake in Angus cattle. 4. Fat EBVs’ influence on fatness fluctuation and supplementary feeding requirements
Beef production systems’ costs are greatly affected by supplementary feed requirements. The inherited ability of cows to gain body condition while pasture is abundant, delaying supplementation onset during pasture shortage was examined. Cows with higher breeding values for fat take longer to require supplementation than cows with lower fat breeding values. Producers can utilise fat breeding values to better match cow genotypes to their production system.
AN13295Divergent genotypes for fatness or residual feed intake in Angus cattle. 3. Performance of mature cows
The impact of selecting for traits such as increased carcass yield and improved feed efficiency in beef cattle on the productivity of the breeding herd is not well understood. This study evaluated the productivity of Angus cows that differed in genetic merit for either subcutaneous Fat or RFI. Clear associations existed between EBVs and cow body composition without significant effects on fertility in mature cows. There is opportunity to exploit genetic variance in traits such as fatness to best suit cow herd management and the target market.
AN15878Effect of Propionibacterium freudenreichii in diets containing rapeseed or flaxseed oil on in vitro ruminal fermentation, methane production and fatty acid biohydrogenation
Strategies that reduce methane production are not only environmentally beneficial, but they also improve the efficiency of ruminant production. Inoculation of a direct-fed microbial, Propionibacterium freudenreichii subsp. shermanii ATCC 8262, did not affect in vitro methane production or fatty acid biohydrogenation in barley silage diets, supplemented with either flaxseed or rapeseed oil. However, supplementing the oils alone did have beneficial effects on fatty acid profiles.
AN15736Effect of protein supplementation in the rumen, abomasum, or both on intake, digestibility, and nitrogen utilisation in cattle fed high-quality tropical forage
Protein degradability can affect forage utilisation and nitrogen retention in beef cattle fed high-quality tropical grass. The present study evaluated how the supplementation with ruminally degradable (RDP) and/or ruminally undegradable protein (RUP) influence forage intake, digestibility, and metabolic characteristics in Nellore bulls. The RDP and RUP supplementation did not affect forage intake and digestibility, but both improved nitrogen retention. However, RUP supplementation presented greater efficiency of nitrogen utilisation likely as a response of different metabolic mechanisms compared to RDP supplementation.
AN15179Extruded full-fat soybean as a substitute for soybean meal and oil in diets for lactating sows: the effect on litter performance and milk composition
Extruded full-fat soybean (EFS), which has high energy content and digestibility, is commonly used in feedstuff for young pigs but restrictedly for sows. This study aimed to investigate the effect of supplementing EFS to the lactation diet on sow and litter performance, and found a positive effect on milk composition and litter performance. This research indicates that supplementing EFS in the sow lactation diet has wide application prospects.
AN15632A review of whole farm-system analysis in evaluating greenhouse-gas mitigation strategies from livestock production systems
Livestock forms an important component of global food production and is a significant contributor to anthropogenic greenhouse-gas (GHG) emissions. This paper reviews how whole farm-system modelling has been used to assess GHG mitigation strategies for livestock production. Whole farm-system modelling provides an effective and efficient means for quantifying the benefits farmers are delivering through changing farm management practices.
AN15850Grazing winter and spring wheat crops improves the profitability of prime lamb production in mixed farming systems of Western Australia
Lamb production in Western Australia has historically been constrained by both within- and between-season fluctuations in pasture productivity and its frequently low availability and poor nutritive value during the autumn-early winter. Hence, there is a need to investigate alternative feed components that could potentially mitigate feed gaps and increase farm profitability. Overall, this study suggests that both winter and spring wheat crops are likely to supply green feed during the winter feed shortage (April–July) and reduce supplementary feed requirements for a short period of time in some seasons.
AN15696Genomic prediction for carcass traits in Japanese Black cattle using single nucleotide polymorphism markers of different densities
Genomic prediction (GP) of genetic merit using single nucleotide polymorphism (SNP) markers can be conducted even when pedigree information is unavailable. In GP performed for carcass weight and marbling score in Japanese Black beef cattle using SNPs of varying densities, around 80% of prediction accuracy was retained when SNPs used were 1/1000 of ~570 000 SNPs available. GP using the lower-density SNP panel may be beneficial to pre-selection for the carcass traits in Japanese Black young breeding animals.
AN15132A quantitative and qualitative approach to the assessment of behaviour of sows upon mixing into group pens with or without a partition
The presence of a concrete partition (a short wall, 2 m long × 1.6 m high) running through the middle of group pens had a positive influence on sow behaviour at mixing. Sows in pens with a partition lay down and stopped investigating or eating/searching for food sooner, and were scored as more ‘calm/relaxed’. Even subtle differences in housing design (in this case, retention of a concrete partition as part of refurbishment) can positively influence the demeanour and activity patterns of sows.
AN16142Evaluation of the effect of a highly soluble calcium source in broiler diets supplemented with phytase on performance, nutrient digestibility, foot ash, mobility and leg weakness
Limestone is a common source of dietary calcium for broilers. Due to its high dietary concentration, calcium binds with phytate, forming insoluble calcium–phytate complexes, thus reducing the bioavailability of both calcium and phosphorus. Replacing limestone with a highly soluble calcium source may allow reduced dietary concentrations of calcium, improving phosphorus digestibility when coupled with exogenous phytase while maintaining bird performance.
AN15651On the profitability of irrigated fodder production: comparative evidence from smallholders in Koga irrigation scheme, Ethiopia
Economically feasible irrigated fodder production can help to manage the problem of livestock feed shortage in subsistent and commercial livestock systems and to diversify farm income. In this study we stochastically simulated profit obtainable from irrigated Rhodes grass seed production to assess the economic feasibility of the practice and to inform related investments and risk management decisions under smallholders’ conditions. The results show the absolute and comparative profitability of the commodity and the possibility to scale out irrigated fodder production both as a source of livestock fodder and farm income.
AN15777Associations between early lactation milk protein concentrations and the intervals to calving for Holstein cows of differing parity
There is a strong negative association between the concentration of milk protein in early lactation and the date of calving of Holstein cows in seasonally calving herds. A difference of 1% in milk protein concentration is associated with a 31–35-day difference in calving date in multiparous cows. Although this difference is less in the calving date of primiparous cows (8 days), some of the factors involved in this association must have influenced the conception patterns of these young cows when they were ~15 months of age and not lactating.
AN16257Effect of in ovo injected prebiotics and synbiotics on the caecal fermentation and intestinal morphology of broiler chickens
The administration of bioactive substances directly into chicken embryo may result in stimulating the favourable bacterial profile in the gut of growing chickens. The main results of the present study show that the injection of beneficial bacteria into the incubating egg together with the substance which stimulates its growth, improved development and physiological functions of the chicken’s digestive tract.
The relationships between pre-mating weight and pregnancy rate were established for Brahman heifers mated as yearlings on improved pasture, and as 2 year olds on native pasture with pre-mating weights recorded in late October/early November and in late December. The relationships were used to produce tables showing the pregnancy rates predicted from different pre-mating weights. These tables will be useful for budgeting and management.
Sexually active bucks induce ovulation in seasonal-anovulatory goats. We determine whether maintaining bucks over 35 days after the introduction of males, would improve pregnancy rate in goats compared with only 15 days. Maintaining bucks with females for 35 days increased pregnancy rates.
AN16166Fetal and lamb losses from pregnancy scanning to lamb marking in commercial sheep flocks in southern New South Wales
Perinatal lamb mortality remains a challenge for sheep producers worldwide. A survey of sheep producers who had pregnancy ultrasound-scanned their ewes was conducted to assess the level of losses for different classes of sheep and any management practices which may influence survival. Our results suggest that perinatal lamb mortality remains a challenge, despite adoption of best practice management.
AN16093Effect of different forage types and concentrate levels on energy conversion, enteric methane production, and animal performance of Holstein × Zebu heifers
Mitigating methane emissions by dietary manipulation is the most attractive mitigation strategy, as the reduction of methane production is associated with improvements in animal productivity. This study was conducted to evaluate the use of sugarcane-based diets as an alternative to corn silage-based diets for heifers on enteric methane production, energy conversion and animal performance. The increased concentrate level in sugarcane-based diets decreases methane emissions per unit of DM intake and body gain, and improves performance of growing heifers.
Quail production is improving in Brazil, but the use of inappropriate strains is one of the factors hindering meat production. We evaluated carcass traits and meat quality of quails from different strains and both sexes pertaining to three breeding-improvement programs. In summary, meat obtained from meat-type strains had better meat quality than that from egg-laying strain. We conclude that meat-type strains, particularly one evaluated, are more appropriate for enterprises focussed on meat production.
AN15369Feedlot performance, carcass characteristics and meat quality of Zebu heifers supplemented with two β-adrenergic agonists
Most research regarding on use of β-agonists is completed utilising Bos taurus cattle. Climatic zone variability in México allows husbandry of both Bos taurus and B. indicus cattle. Export of calves of European breeds to the USA is a profit centre for Mexican cow–calf farmers, leaving the Zebu heifers for Mexican feedlots. Thus, impacts of supplementation of β-agonists to Zebu females is of great importance in nutritional management programs in the Mexican beef industry.
AN16202Effects of wet feeding and enzyme supplementation on nutritional value of wheat screenings for broiler chickens
Wheat screening (WS) is a cheap source of energy and other nutrients for use in broiler diets; however, it has a considerable amount of non-starch polysaccharides (NSP). The negative effects of NSP may be decreased by the supplementation with exogenous enzymes and/or with wet feeding of wheat-based diets. In the present study, broiler performance was improved by the inclusion of WS to the diet and also by wet feeding, but not by enzyme supplementation.
Little is known about the acceptability of broiler hen meat. This study evaluated the effect of age and aging time on breast meat properties. Its use is beneficial because it has more fat and less cholesterol, higher intracellular water-holding capacity, and lower cooking loss than meat from commercial broilers, and is less susceptible to lipid oxidation. Aging breast fillets for 3 days at 2°C is sufficient to tenderise the poultry meat and reduce the amount of fat and cholesterol.
An in-depth understanding of energy and protein partitioning, underpinning nutrient utilisation, is pivotal for allowing predictions of growth in animals based on knowledge of nutrients in diets. A construct to allow a logical quantitative study of nutrient partitioning in the growing animal from a causal perspective is discussed. Gaps in current knowledge are identified.
The prediction of feed intake is important in poultry production. To include environmental effects on feed intake is necessary to calculate the daily total heat production. The present study showed that the re-parameterisation of heat-loss equations are efficient to predict the heat flux in broilers under different environmental conditions.
Managing risk is a key part of farming. Sources of risk include business risks (such as fluctuating commodity and input prices) and financial risks (the risk that cash flow will not meet debt obligations). A farmer has little control over business risk but does have some control over financial risk (a farmer can control how much they borrow). The present study sought to identify the contribution of business and financial risk on a farm business. It demonstrated that detailed financial analysis should be included when analysing changes to farm systems.
AN16170Field storage conditions for cattle manure to limit nitrogen losses and optimise fertiliser value
The use of organic manure is an issue of debate and controversy in environmental policy in many countries, and field storage is often restricted out of fear for nutrient losses. We investigated different storage options to reduce soil nitrogen losses, meanwhile optimising manure quality, and found that a maximum of 4% of the initial nitrogen content was lost by leaching, depending on the initial manure characteristics and storage option. These findings could help policymakers in adapting regulations regarding field storage, and practitioners in optimising manure treatment.
AN16079Revisiting summer infertility in the pig: could heat stress-induced sperm DNA damage negatively affect early embryo development?
While summer infertility, which costs the industry millions, has traditionally been considered a sow problem, recent studies demonstrate that DNA damage in sperm caused by heat stress can result in early embryo loss in mice. This article proposes a role and mechanism by which heat stress-induced DNA damage in boar sperm may significantly contribute to downstream pregnancy failure in the sow during summer. Confirming such a link will enable development of boar management strategies to mitigate summer infertility.
AN15768Feeding management, production and performance of 13 pasture-based dairy farms in a Mediterranean environment
Supplementary feeding practices on Western Australian dairy farms are an important factor affecting productivity and profitability. Farmers in the region generally provide concentrates to cows in the milking parlour, but some also offer mixed rations with forages and concentrates outside the parlour. Our data indicate performance was highly variable between farms and systems, and mixed ration feeding systems did not increase intake or milk production. Management appears to have a greater influence on farm performance than feeding system per se.
AN15460Achieving better strategic fit and higher surplus for Australian beef value chains by recognising and countering chain failure
Food value chains have to decide whether they will supply basic quality goods at lowest cost or supply goods with additional attributes that consumers value more but that are more costly to provide. The objective of this study was to develop an economic framework that allows food value chains to make the most profitable choices. Our analysis showed that such a framework could be developed but that practical implementation would require some new measurements of whole-of-chain outcomes so that the economic relationships making up the framework could be estimated and analysed.
AN16213Identification of peptides in the terminal ileum of broiler chickens fed diets based on maize and soybean meal using proteomics
Protein that leaves the intestine represents a net loss to the animal, reduces efficiency of digestion and may compromise environmental sustainability. The protein that leaves the intestine is of mixed origin, being partially undigested dietary protein and partly proteins of endogenous origin, e.g. various intestinal secretions. Data presented herein sheds light on the specific origin of the proteins in the intestine and will help nutritionists develop strategies to recover a greater proportion of these recalcitrant protein fractions.
AN15535Efficiency of rumen microbial protein synthesis in cattle grazing tropical pastures as estimated by a novel technique
Increasing the efficiency of microbial protein synthesis (EMPS) in the rumen of cattle grazing tropical pastures is important as microbial protein provides most of the metabolisable protein supplied to the animal and therefore has a significant effect on the growth rate of the grazing animal. Our study showed that EMPS in steers consuming tropical grass pastures was low and limited by rumen degradable protein supply from the pasture. High EMPS was associated with very high rumen degradable protein levels in the pasture, vastly in excess of the requirements of the rumen microbes.
AN15474How dietary cottonseed hull affects the performance of young bulls finished in a high-concentrate system
The cottonseed hull could be useful in high-concentrate systems to improve beef production. This study aimed to evaluate the effects of cottonseed hull in concentrations 210–330 g/kg on a DM basis of high-concentrate diets on feed intake, in vitro digestibility, animal performance, carcass weights and ingestive behaviour of young bulls. A cottonseed hull level up to 270 g/kg of dietary DM does not have detrimental effects on animal performance when utilised as a non-forage fibre in high-concentrate diets to young bulls in feedlots.
AN15709Cottonseed meal is a suitable replacement for soybean meal in supplements fed to Nellore heifers grazing Brachiaria decumbens
An important source of protein used in the diets of animals of production is soybean meal, which can present high prices. Cottonseed meal could be a suitable replacement to soybean meal in supplements to grazing beef cattle. This study evaluated the effect of substituting soybean meal with cottonseed meal in supplements fed to grazing heifers. No relevant differences were found in animal performance, indicating that cottonseed meal can be a suitable and possibly cheaper replacement to soybean meal.
AN15480Influence of the housing environment during sow gestation on maternal health, and offspring immunity and survival
In pig husbandry, pregnant females are often exposed to stressful conditions that may affect their physiology, behaviour or health. In this study, housing sows in different systems during gestation (conventional vs enriched) modulated their salivary cortisol and health status during gestation and their piglet pre-weaning mortality, despite the comparable environments from farrowing to weaning. This suggests that optimising housing in order to reduce the level of stress of pregnant sows may be also beneficial for the survival of their piglets after birth.
AN15574Impact of liveweight, fat and muscle sire breeding values on ewe reproduction is minimal but variable across Australian grazing systems
Australian sheep producers have the potential to improve reproductive rates through optimising ewe body condition across the production cycle. Reproductive records from the Information Nucleus Flock and Sheep Genetics datasets were analysed to examine the influence of sire breeding values for liveweight, fat and muscle across a variety of production environments. The sire breeding values for liveweight, fat and muscle had very little association with the reproductive performance of their daughters, on average, but the association varied across flocks from unfavourable to favourable.
AN15799Effect of bedding materials during transport on welfare indicators and microbiological quality in lambs
This research tackles the welfare of lambs during transport to slaughterhouse and its implications on the hygienic quality of the carcass. It specifically focuses on the bedding material required for the transportation of the animals and can be taken as a base to drive future legislations integrating the whole production system. Regarding the results, no significant differences have been found among the materials tested (sawdust rice husk, and double layer of sawdust).
AN16048A regional model of sheep lice to study the effect on lice prevalence and costs for Australian farms using a range of treatment efficacy in combination with other lice control strategies
A model of the Australian flock prevalence of lice was used to examine the value of various methods of treating sheep for lice after shearing when combined with other lice management options. The model showed that high-cost treatment could be cost-effective provided it resulted in eradication, and should be combined with adequate biosecurity for purchased sheep. These two methods in combination could provide a dramatic reduction in lice prevalence and in costs associated with lice.
AN15810Carcass composition and quality of meat from Pekin ducks finished on diets with varying levels of whole wheat grain
The desire to minimise production costs has renewed interest in using diets with whole cereal grain in commercial poultry production. Diet dilution with whole wheat grain was beneficial to the economics of broiler duck production while maintaining good carcass quality. The effect on meat quality was inconsistent.
AN15565Ractopamine with dietary lysine concentrations above basal requirements of finishing barrows improves growth performance, carcass traits and modifies the mTor signalling pathway
The use of ractopamine and the possible cellular pathway it takes in order to improve pig performance and characteristics are still the focus of discussion. Differences in performance and intracellular protein expression were assessed, and the mTOR signalling pathway was activated by ractopamine. This finding indicates that the increased protein expression seen when ractopamine is used is probably due to the mTOR activation.
AN16211A comparison of the growth of Brahman and F1 Senepol × Brahman steers in an Indonesian feedlot
This study found that F1 Senepol × Brahman steers had a higher growth rate than Brahman steers in an Indonesian feedlot. The study was conducted to address concerns that crossbred cattle are discriminated against by live export cattle buyers due to a perception that they do not perform as well as Brahmans in Indonesian feedlots. These results should reduce discrimination against Brahman × tropically adapted Bos taurus crossbreds in the live export market.
AN14862Effect of long-term rumen-protected methionine supplementation on performance of Shami goats and growth performance of their kids
An experiment was conducted to evaluate the effect of rumen-protected methionine on performance of late pregnant and early lactating goats and growth of their suckling kids. Seventy-five goat dams were divided into three equal groups and supplemented with 0, 2.5, or 5 g/head.day. Supplementation with RPM increased milk production and milk protein content with no changes in milk fat content. Growth performance and birth weights of born kids were not affected.
AN15321Impact of young ewe fertility rate on risk and genetic gain in sheep-breeding programs using genomic selection
The impact of young-ewe fertility rate, selection age and genomic information on genetic gain in sheep-breeding programs was evaluated using stochastic simulation. Yearling-ewe fertility level, ram and ewe age and the availability of genomic information all significantly (P < 0.05) influenced genetic gain. On average, at fertility levels of 10% and above in yearling ewes, flock genetic progress is unlikely to be adversely affected and there is no increase in breeding-program risk.
Dairy cows are in some ways very much like human consumers; they select from among a variety of foods on the basis of the nutritive characteristics of those foods. When a cow is offered two oaten hays simultaneously, we provide a means of predicting how much of each hay will be consumed. Accurate prediction of hay intake will enable the selection of a set of hays that maximises the nutritive value of what dairy cows consume, and thereby maximises milk production.
AN15865Growth performance, carcass traits, behaviour and welfare of New Zealand White rabbits housed in different enriched cages
From the last decade and onward, consumers are interested in obtaining high-quality products from animals reared and kept under a high welfare environment. We aimed to investigate the impact of gnawing sticks (of apple or willow tree) as environmental enrichment on the performance, carcass traits and behaviour of individually housed growing rabbits. Enriched cages increased the final bodyweight, some carcass traits, and reduced abnormal behaviour, and potentially improved rabbit welfare in intensive rabbit breeding.
AN15184Relationships between the activity of respiratory-chain complexes in pre- (biopsy) or post-slaughter muscle samples and feed efficiency in random-bred Ghezel lambs
Feed efficiency can be more accurately estimated by measuring the residual feed intake (RFI), which is laborious and time-consuming. Physiological criteria for RFI determination would facilitate genetic selection for feed efficiency using RFI. We found that mitochondrial enzyme activity measured in biopsied muscle samples provides a useful procedure for genetic selection of lambs for this component of feed efficiency.
It is important to find alternative feed resources as sources of protein in rations of beef cattle to improve nutrient digestibility. This study evaluated the effect of yeast-fermented cassava root (YEFECAR) as a feed ingredient in the concentrate diet in beef cattle. Results show that YEFECAR at 20% in concentrate feed tended to enhance fibre digestibility in cattle.
AN16126Effects of dietary selenium-yeast concentrations on growth performance and carcass composition of ducks
The effects of selenium (Se)-yeast diet supplementation on performance and carcass composition in ducks has great importance in the production of meat and functional foods. This study shows that a diet containing 0.4 mg of added Se per kilogram produced the greatest growth-performance results in ducks. The highest dietary supplementation level of Se did not improve performance.
Hay, an essential component of dairy cow rations, is required for rumen function and milk fat. Testing the influence of fibre and sugars on a cow’s decision to choose between hays showed that the fibre content of the hay was a dominant factor and further, decisions made in the first 30 min were indicative of longer-term choice; composition of total hay intake also contributed to choice. The results provide a basis for improved ration formulation.
Return on investment from animal research in Australia is about half that from investment in crop research. These returns could be improved by (1) selection of more appropriate areas for research, (2) adoption and consistent application through a risk-control system of a small number of processes that, if not performed correctly, will have large impacts on productivity and (3) strict adherence to the scientific method. Future application of electronic technologies for measurement, interpretation and control of farm processes in real-time through web-based systems will enhance productivity and free managers from day-to-day operations for long-term strategy development.
AN15708Inhibitions of FASN suppress triglyceride synthesis via the control of malonyl-CoA in goat mammary epithelial cells
Inhibition of fatty acid synthase (FASN) by C75, a synthetic inhibitor, could significantly reduce the relative content of monounsaturated fatty acids (C16:1 and C18:1) in goat mammary epithelial cells. Both C75 and shRNA downregulated the mRNA expression of GPAM, AGPAT6 and DGAT2 relating to triglyceride synthesis, which was in accordance with the results of malonyl-CoA treatment. The malonyl-CoA demonstrated the important role in regulating triglyceride synthesis by inhibiting the expression of FASN.
Discharge of huge amount of wastewater is the greatest obstacle to the development of sustainable pig farming in the developing countries in Asia, which are experiencing a rapid expansion in this industry. Although converting this organic waste into renewable energy seems to offer an attractive option to the abovementioned problem, ~60% of the biogas digesta still remain and need to be discharged to the environment. The present paper reviewed our approach, which was shown to significantly cut down the usage of water and the discharge of wastewater, with nearly 98% of biological oxygen demand removed.
AN15608Influence of climate variability and stocking strategies on greenhouse gas emissions (GHGE), production and profit of a northern Queensland beef cattle herd
Studies of greenhouse gas emissions (GHGE) in agriculture rarely account for the variation that occurs due to seasonal conditions. This study quantified the effects of climate variability and stocking strategies on GHGE and profit of a northern Queensland beef herd. Moderate stocking rates had the lowest GHGE intensity and highest profit, supporting previous work that recommends similar stocking strategies in the region.
The people of the world demand high-quality diets containing animal products, and the demand for those products is projected to increase; meeting that demand requires improved efficiency of use of valuable feedstuffs. Achieving those improvements is complicated by the complexity of animal biology, but that complexity can be addressed in silico through mechanistic simulation models. Future models should be directed to effects of disease, activation of the immune system, various stressors and health-improving technologies.
AN15766Updated predictions of enteric methane emissions from sheep suitable for use in the New Zealand national greenhouse gas inventory
The present study analyses New Zealand data on methane emissions from sheep fed fresh grass-based diets, collected between 2009 and 2015, where emissions were measured using respiration chambers. Dry matter intake alone was found to be a good predictor of emissions, although in animals <1 year of age the inclusion of dietary metabolisable energy concentration in addition to dry matter improved predictions.
AN15705Optimal dose of 3-nitrooxypropanol for decreasing enteric methane emissions from beef cattle fed high-forage and high-grain diets
Dietary supplementation of 3-nitrooxypropanol (NOP) has been suggested as an effective strategy to lower enteric methane (CH4) emissions from ruminants. Results from the present study further support the efficacy of NOP in lowering CH4 emissions. Among various dose levels investigated in the present study, NOP supplemented at 100, 150 and 200 mg/kg DM was the most effective in decreasing CH4 emissions in steers fed high-forage and high-grain diets, without inducing any negative effects on intake.
Artificial pollen substitutes are needed to improve honeybee productivity in periods of nutrient scarcity during droughts, wet weather, gaps in floral sources and when bees are working eucalyptus flows with limited- or poor-quality pollen. Ingredients meeting honeybee nutrient requirements were screened for attractiveness and tested as a sole nutrient source. Bee-collected pollen outperformed the artificial substitutes and further modification to the substitutes is required.
AN15597Methane emissions differ between sheep offered a conventional diploid, a high-sugar diploid or a tetraploid perennial ryegrass cultivar at two allowances at three times of the year
Methane production of sheep in pastoral systems is a major contributor to total greenhouse gasses produced in New Zealand. Elevated water-soluble carbohydrate concentrations, as in high sugar (HSG) and tetraploid (TRG) ryegrass, may affect rumen fermentation and reduce methane production per unit of intake, as found in this study for sheep fed HSG and TRG. However, the effect was not consistently associated with either cultivar and could not be attributed to higher forage water-soluble carbohydrate concentrations.
AN15646Thai native chicken meat: an option to meet the demands for specific meat quality by certain groups of consumers; a review
The sensory preference of consumers in Thailand does not always coincide with the meat produced with commercial, fast-growing broiler lines. Native breeds offer an alternative with a chewier meat and special appearance and flavour features. The review compiles information available about Asian breeds in comparison with fast-growing broilers concerning meat-quality traits.
AN15692Effect of the ratio of maize cob and husk to napier Pakchong 1 silage on nutritive value and in vitro gas production of rumen fluid of Thai native cattle
Pakchong 1 napier grass is a new hybrid napier with high yield and suitable for silage making but its moisture content is too high. Therefore, it should be mixed with an absorbent, such as maize cob and husk. We found that recommended ratio of maize cob and husk mixed with Pakchong 1 napier grass is 1 : 10 and ensiling fermentation can increased the proportion of protein in the roughage.
AN15586Greenhouse gas emission intensity based on lifetime milk production of dairy animals, as affected by ration-balancing program
Livestock contributes to global warming by emission of greenhouse gases (GHGs). In the process of fermentation of feed in the fore stomach, dairy animals produce methane. Majority of dairy animals in developing countries are fed on rations imbalanced in nutrients. As a result, animals on such rations produce more methane per litre of milk. On feeding balanced rations, animals produce less enteric methane and manure nitrous oxide. Thus, balanced feeding could be a promising strategy for reducing GHGs emission intensity.
Chronic inflammation is a common yet underappreciated feature of intensive livestock production systems and is also associated with exposure to high environmental temperatures. Recent research in the medical field has shown that methyl donors can prevent or ameliorate inflammatory diseases such as fatty liver and enteritis. It is proposed that supplementation of livestock diets with methyl donors such as betaine, choline or folate may be effective in the prevention and treatment of chronic inflammation and associated diseases in livestock.
AN15684In vitro rumen fermentation characteristics of goat and sheep supplemented with polyunsaturated fatty acids
Research data showed inconsistencies in digestive capacity between goat and sheep. Results of the study showed significantly higher in vitro gas-production rate constant for insoluble fraction (c), in vitro organic matter digestibility (IVOMD) and volatile fatty acids (VFA) production in rumen fluid of goat than sheep. The higher fermentative capacity of goat suggests the advantage of keeping goats in environment with poor feed resources.
Recent findings have suggested that direct-fed microbials can affect gut microbiota that play a fundamental role in enhancing performance and health of chickens. We attempted to further characterise the functions of direct-fed microbials as therapeutic, prophylactic and growth-promotion uses in the poultry industry. The present review highlights that dietary direct-fed microbials can affect host–microbe interaction, shaping host immunity towards increasing resistance of chickens to enteric diseases.
AN15610Impact of phytogenic feed additives on growth performance, nutrient digestion and methanogenesis in growing buffaloes
Methane emissions from ruminant livestock (cattle, buffalo, sheep and goat) were estimated at ~2.2 billion tonnes of carbon dioxide equivalent, accounting for ~80% of agricultural methane and 37% of the total anthropogenic methane emissions. The present study was designed to evaluate the effects of plants as methane inhibitors in growing buffaloes. Methane emission was inhibited by ~10–18% in the supplemented groups. Further, long-term experiments should be conducted to validate these findings before they can be recommended for use at a field level.
AN15638Greenhouse gas emissions from dung, urine and dairy pond sludge applied to pasture. 2. Methane emissions
The greenhouse gas methane can be absorbed or emitted by soil while cattle wastes deposited onto the soil can be a source. In field studies, the effect of applications to pasture of dung and dairy sludge on net methane emissions to the atmosphere were examined. Measured emissions were mostly lower than those currently used in the current Australian estimates for emissions from dairy cow dung in temperate Australia.
AN15595Greenhouse gas emissions from dung, urine and dairy pond sludge applied to pasture. 1. Nitrous oxide emissions
In Australia, animal excreta deposited onto pasture by grazing livestock is a major source of nitrous oxide, a potent greenhouse gas. Field studies found that emissions of nitrous oxide from excreta could be reduced by up to 59% by the application of the chemical inhibitor, nitrapyrin. Nitrapyrin was found to be an effective tool in reducing emissions from dung, urine and dairy sludge and was most effective on wet soils.
Cattle emit methane, a greenhouse gas, which is usually measured in specialised facilities over 2 or more days. We have demonstrated that the measurement can be done in 1 day with less than 5% loss in accuracy. The resulting increase in throughput of the facilities means that more cattle can be measured for this important gas.
AN15757Enzyme- and gene-based approaches for developing methanogen-specific compounds to control ruminant methane emissions: a review
Methane emissions from ruminants are a significant contributor to climate change and are produced by archaeal methanogens. Due to their unusual metabolism, gene- and enzyme-based techniques can be used to develop methanogen-specific inhibitors, using strategies similar to those employed to develop anti-cancer drugs. We review previous research that has incorporated chemically defined inhibitors against methanogens and discuss the impacts on future control of ruminant methane emissions.
AN15702Comparison of aquaporin-1 expression between yak (Bos grunniens) and indigenous cattle (Bos taurus) in the Qinghai–Tibetan Plateau
Comparative study between yak and cattle can provide information on animal adaptation to high altitude. This is a preliminary study on water channels in yaks, which we found were somewhat different from that in indigenous cattle. This discovery could provide a new perspective to explain some adaptive mechanisms, especially the water modulation and balance, of yaks to the harsh alpine environment and may help to improve the current understanding of altitude sickness in humans.
AN15392Effect of volume of urine and mass of faeces on N2O and CH4 emissions of dairy-cow excreta in a tropical pasture
CH4 and N2O emissions from bovine dung-N are linearly correlated with faeces weight. N2O emission factor of urine is reduced with urine volume. N deposited as urine is a much greater N2O source than is faeces-N.
AN12428A review of factors influencing key biological components of maternal productivity in temperate beef cattle
Cow–calf efficiency or maternal productivity is highly correlated with total system efficiency of beef production and needs to be balanced with modern consumer requirements. This review examined the key biological components of maternal productivity that were used as a guide for determining the appropriateness of different maternal productivity definitions. The recommended definition focuses on the cow–calf unit and possesses the capacity to facilitate improvements in beef-production efficiency.
AN14034Divergent breeding values for fatness or residual feed intake in Angus cattle. 5. Cow genotype affects feed efficiency and maternal productivity
A current concern of Australian commercial cattle producers is that selection for increased feedlot performance is leading to reduced productivity in the cow herd. Under low nutrition cows with high genetic rib fat had higher maternal productivity than those with low rib fat due to increased weaning rates. Cows selected for low residual feed intake had higher maternal productivity than high residual feed intake cows due to lower feed intake. In this context, including low residual feed intake and increased reproduction should be considered in a balanced beef breeding program.
AN15533Liveweight gain and urinary nitrogen excretion of dairy heifers grazing perennial ryegrass-white clover pasture, canola, and wheat
Previous work has shown canola and wheat have potential as dual-purpose crops to support animal liveweight gain and grain production in animals other than dairy heifers. Limited information is available regarding the use of canola and wheat to support dairy heifer production and its effect on environment sustainability. This study investigated liveweight gain and urinary nitrogen excretion of dairy heifers grazing canola and wheat in comparison to perennial ryegrass-white clover pasture. The results indicate that canola and wheat can sustain heifer liveweight gain, while potentially reducing nitrous oxide emissions and nitrate leaching compared with pasture.
AN15563Changes in feed intake during isolation stress in respiration chambers may impact methane emissions assessment
Methane, a major greenhouse gas emitted by livestock, requires robust methods of measurement in order to identify new and appropriate mitigation strategies. This study demonstrates that isolation within respiration chambers, the current most precise method of methane measurement in livestock, could underestimate emissions due to a reduction in feed intake. If changes in behaviour and physiology due to isolation stress are modelled, this would refine estimations of livestock greenhouse gas emissions that will help to find the most appropriate measures to mitigate climate change.
AN13023Selection for increased muscling is not detrimental to maternal productivity traits in Angus cows
Sale value of cattle may improve with greater muscling, but it is important to establish whether maternal productivity is maintained. This research showed that selection for increased muscling in Angus cows was not detrimental to maternal productivity under average to good nutritional conditions. Beef producers can confidently increase muscling in British type cows to benefit from price premiums without reducing their maternal ability.
These articles have been peer reviewed and accepted for publication. They are still in production and have not been edited, so may differ from the final published form.
Variability of the IGF2 locus in the Suino Nero Lucano pig population and its effects on meat quality
Effect of Glycerol Supplementation on Lactation Performance, Nutrient Digestibility, and Blood Metabolites in Early Lactation of Dairy Buffaloes
Impact of Dietary Carbohydrate Balance on Rumen Fermentation, Eating Behaviour, Growth, and Development of 8 to 10 Months Old Heifers
Pregnancy establishment and maintenance after the administration of equine chorionic gonadotropin (eCG) associated or not with GnRH after insemination in sheep
Consequences of genetic selection for environmental impact traits on economically important traits in dairy cows
Effects of phosphorus supplementation in high-grain diets on blood, chemical and physical parameters of bones of feedlot Nellore bulls
Effect of zinc concentration and source on performance, tissue mineral status, activities of SOD enzyme and lipid peroxidation of meat in broiler chickens
Effect of prepartum supplementation with niacin, choline and cod liver oil on postpartum insulin sensitivity and the redox status in cows with subclinical ketosis
Supplementation with N-carbamylglutamate and vitamin C: improving gestation and lactation outcomes in sows under heat stress
Systems impacts of introducing crop grazing into pasture-based systems – the McClymont Memorial Lecture
Effects of hydrated sodium calcium aluminosilicate on growth performance, fatty liver, intestine morphology, and serum parameters of overfed geese
Effects of drinking saline water on food and water intake, blood and urine electrolytes and biochemical and hematological parameters in goats: a preliminary study
Compositional, organoleptic, metabolic enzyme activity and fibre characteristics of muscle from bulls with different growth paths to a common carcass weight
Impact of zilpaterol hydrochloride and soybean oil supplementation on intramuscular fat, fatty acid profile and cholesterol concentration in the Longissimus muscle of male hair lamb under moderate heat stress conditions
Improving forage nutritive value and botanical composition in a natural grassland using different grazing methods and herbage allowances
Post experimental modelling of grazing systems to improve profit and environmental outcomes using AusFarm
Isolation and characterization of acid and pepsin soluble collagen from the skin of Cervus korean TEMMINCK var. mantchuricus Swinhoe
Carcass and meat properties of six genotypes of young bulls finished under feedlot temperate conditions of Mexico
Estimation of genetic parameters for test-day milk yield and fat percentage in first calving Iranian buffaloes
Fasciola gigantica infection in large ruminants in northern Laos: smallholder knowledge and practices
The effects of barley replacement by dehydrated citrus pulp on feed intake, performance, feeding behaviour and serum metabolic indicators in lambs
Close contact with spontaneously cycling Saint Croix ewes triggers cyclic activity in seasonally anestrous Suffolk ewes
Habitat preference and Feeding Ecology of Alpine Musk Deer (Moschus chrysogaster) in Kedarnath Wildlife Sanctuary, Uttarakhand, India
The effect of the level and feeding duration of spray-dried plasma protein on growth performance, digestive enzyme activities, nutrient digestibility, and intestinal mucosal development of broiler chickens
Getting the most out of advanced farm management technologies: Roles of technology suppliers and dairy industry organisations in supporting precision dairy farmers
Patterns of milk production, blood metabolite profile and enzyme activities of two fat-tailed sheep breeds
Divergent breeding values for fatness or residual feed intake in Angus cattle.6.Dam line impacts steer carcass compliance
Divergent breeding values for fatness or residual feed intake in Angus cattle. 1. Pregnancy rates of heifers differed between fat lines and were affected by weight and fat.
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