Animal Production Science
Volume 57 Number 8 2017
RESEARCH FRONT: Sustainable Animal Agriculture for Developing Countries 2015
ANv57n8_FOForeword: ‘Sustainable Animal Agriculture for Developing Countries 2015’
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
The peer-reviewed and edited version of record published online before inclusion in an issue
AN15758Effect of zinc concentration and source on performance, tissue mineral status, activity of superoxide dismutase enzyme and lipid peroxidation of meat in broiler chickens
Zinc is crucial for a wide variety of physiological processes in all animals. The aim of this experiment was to assess the levels and zinc sources effect on broiler chicken performance. Results demonstrated that supplementation diet with 50 mg of organic Zinc may be sufficient for normal broiler growth to 28 days of age.
AN16143Isolation and characterisation of acid- and pepsin-soluble collagen from the skin of Cervus korean TEMMINCK var. mantchuricus Swinhoe
The present study investigates an alternative source of collagen from a deer skin for industrial applications. Acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from the skin of Cervus korean TEMMINCK var. mantchuricus Swinhoe were isolated and characterised and found to possess similar characteristics to bovine-derived collagens. Therefore, dear skin collagen may exert the same properties as other well-known mammalian collagens in industrial applications.
AN16592Consequences of genetic selection for environmental impact traits on economically important traits in dairy cows
Selecting for environmental impact traits might have consequences we do not know currently. This study tried to get a first glimpse of what might be expected as correlated responses from currently selected traits. Because of the complexity of relationships among all the traits we want to improve, results showed that profound changes in current indexes might be required, not only simply adding environmental traits.
AN17003Effects of phosphorus supplementation in high-grain diets on blood, chemical and physical parameters of bones of feedlot Nellore bulls
Bone growth is directly correlated to mineral nutrition, with emphasis on phosphorus (P) under Brazilians conditions. We evaluated the effect of P supplementation in high-grain diets on blood, chemical and physical parameters of bones of feedlot Nellore bulls. P concentration of 2.4 g/kg in DM was adequate to ensure health and its supplementation resulted in no benefits in neither chemical nor physical properties from bones of feedlot Nellore cattle, with emphasis for the increase of pollution and economic losses in Brazilian feedlots.
Many producers avoid grazing vegetative cereal crops with reproducing ewes because of a suspected risk of metabolic disease. Monitoring of the mineral status of wheat, oats and barley, and of the pregnant ewes grazing these crops indicated an imbalanced mineral supply from crops and consequent low mineral status of ewes on some farms. Strategies to minimise the risk of hypocalcaemia and hypomagnesaemia are required.
AN16011Detection of heat produced during roughage digestion in ruminants by using infrared thermography
Infrared thermography contributes to animal nutrition studies as a non-invasive tool to capture heat digestion in ruminants. Infrared thermography was able to detect differences in the body temperature of animals associated with different fibre proportions in the diets. The sensitivity of infrared thermography in capturing small temperature variations and its non-invasive nature make it a useful tool in different fields of study that require the measurement of temperature differences of objects, plants, animals or humans.
AN16129Post-experimental modelling of grazing systems to improve profit and environmental outcomes using AusFarm
Assessments of grazing systems are often constrained by management decisions and seasonal conditions, which can lead to conflicting results when comparing systems. This paper used post-experimental modelling to gain a better understanding of the influence climate and management decisions can have over a long-term period. In understanding the impact of these management decisions and climate influences, strategies can be developed to improve management of the system.
Grazing by sheep and cattle has reduced productivity and increased soil erosion and loss of perennial grasses in the native grasslands of southern Australia. Large-scale grazing experiments produce reliable information on interactions between plant and livestock needed to identify the best management for farmers to use to improve their grasslands. This special edition of Animal Production Science provides recommendations to help farmers improve production and environmental benefits of native pastures.
AN16842Effect of prepartum supplementation with niacin, choline and cod liver oil on postpartum insulin sensitivity and the redox status in cows with subclinical ketosis
The interest in improving periparturient health through dietary supplements has received great attention in recent years. The purpose of this study was to compare the effects of niacin, choline and cod liver oil on metabolic variables, and indices of insulin sensitivity in cows with subclinical ketosis. The findings of this study suggest benefits of prepartum supplementation to cattle with subclinical ketosis and could support the advancement of future investigations in animal production.
We have developed a gene technology that allows specific marking of the sex-determining chromosome in chickens so that the males can be identified before hatching and removed before incubation. This provides a simple solution to meet a pressing need for the industry and a leading opportunity for the adoption of biotechnology in animal agriculture.
AN16489Pregnancy establishment and maintenance after the administration of equine chorionic gonadotropin (eCG) associated or not with gonadotropin-releasing hormone (GnRH) after insemination in sheep
The administration of equine chorionic gonadotropin (eCG) or gonadotropin-releasing hormone (GnRH) during the luteal phase promote serum progesterone concentrations in ewes. We evaluate pregnancy rate obtained with eCG and/or GnRH treatment after FTAI. The eCG administration on Day 10 after FTAI had a marginal positive effect on pregnancy establishment during the first month, which was not maintained during the second month of gestation. No effect of GnRH treatment on Day 6 and 11 was found.
Current methods for estimating energy intake and expenditure of ruminants in the field have a range of technical problems. The open-circuit gas-quantification system (GQS) provides a simple, alternative means of quantifying energy intake and expenditure in the field. The potential for GQS to estimate intake represents an important potential breakthrough for identifying and selecting cows with greater feed efficiency in grazing systems.
Genetic selection can greatly increase fertility, which is a major profit driver in northern Australian beef enterprises, but to do so a cow’s calving date is required. Traditionally the calving date is recorded using laborious and costly methods, however, results show that the date can be automatically recorded using a remote weighing system. This will enable seedstock producers to more easily record the calving date, therefore, increasing the recording of fertility traits and consequently increasing the profitability of beef producers in northern Australia.
AN16781System impacts of introducing crop grazing into pasture-based systems: the McClymont Memorial Lecture
Using a dual-purpose crop within a grazing system could greatly increase productivity but requires careful management. The paper reviews crop grazing and shows that it can greatly increase livestock feed supply with minimal effect on crop yield; livestock grazing wheat require supplementation with sodium and magnesium. In future, more work is required with grazing ewes, with cattle and with wool-producing systems.
Endoparasite and nutritional statuses of Suffolk lambs were compared across a range of production systems in subtropical conditions of Brazil. The weaned-feedlot lambs and those in the controlled-suckling systems presented the best performance, and the animals in creep-feeding and creep-grazing had the best overall performance on pasture. Production systems exert a major influence on lamb performance, mainly when the ewe is present and supplementation is given on pasture. Nutritional status in different production systems may support overcoming the challenge caused by gastrointestinal nematodes.
AN16118Impact of dietary carbohydrate balance on rumen fermentation, eating behaviour, growth and development of 8–10-month-old heifers
As is known to all, milk has a great influence on our health, so we should pay attention to the feeding and management of dairy cows. The present study indicated that the novel carbohydrate balance index, ‘CBI’, may regulate the growth and development of cows. In future work, the CBI level may be applied in feed formulation for dairy cows.
AN16830Compositional, organoleptic, metabolic enzyme activity and fibre characteristics of muscle from bulls with different growth paths to a common carcass weight
The effect of growth path to slaughter on the quality of beef from suckler bulls raised in a temperate grass-based production system has not been widely studied. This study has shown that increasing the growth of bulls during the winter, above that advised for steers, has no commercially relevant effect on the sensory characteristics of beef. Producers therefore can economically optimise the growth path of bulls without concern for a deleterious effect on beef quality.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Starch and protein digestive dynamics in low-protein diets supplemented with crystalline amino acids
Feeding wet distillers grains plus solubles contributes to sarcoplasmic reticulum membrane instability
Recombinant bovine somatotropin on heifer’s biometric measures, body weight, blood metabolites, and dry matter intake predictions
Effect of individual Ayurveda plants and mixtures thereof on in vitro ruminal fermentation, methane production and nutrient degradability
Genotype by environment interaction for yearling weight in Nellore cattle applying reaction norms models
Effect of Nano-Selenium and Nano-Zinc particles during in vitro maturation on the developmental competence of bovine oocytes
Segmentation of Australian meat consumers based on attitudes regarding farm animal welfare and the environmental impact of meat production
Efficacy of antioxidant and antimicrobial activity of whole porcine blood hydrolysates and its fractions under in-vitro conditions
Growth performance and carcass characteristics of Australian prime lambs supplemented with pellets containing canola oil or flaxseed oil
Herd dynamics reflect constraints for pig production and farmer attitudes in smallholder systems in Lao PDR
Assessing the profitability of native pasture grazing systems: a stochastic whole-farm modelling approach
The effect of lipid metabolism-related genes on intramuscular fat content and fatty acid composition in multiple muscles
Comparisons of meat quality and muscle fiber characteristics on multiple pig breeds and sexes using principal component analysis
Effect of the inclusion of natural additives on animal performance and meat quality of crossbred bulls (Angus × Nellore) finished in feedlot
Qualitative characteristics of meat from triceps brachii muscle from steers and heifers finished on high-concentrate diets containing increasing concentrations of linseed oil
A non-synonymous single nucleotide polymorphism in the paraoxonase 3 gene regulates meat quality in Berkshire pigs
Differences on meat colour and composition between “Landrace × Large White” and “Iberian” pigs under identical nutritional and management conditions
Protective effects of taurine on growth performance and intestinal epithelial barrier function in weaned piglets challenged without or with lipopolysaccharide
Evaluating the influence of dietary phytogenic blends on gestating and lactating sows and suckling piglets
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
Effect of zinc concentration and source on performance, tissue mineral status, activities of SOD enzyme and lipid peroxidation of meat in broiler chickens
Supplementation with N-carbamylglutamate and vitamin C: improving gestation and lactation outcomes in sows under heat stress
Effects of hydrated sodium calcium aluminosilicate on growth performance, fatty liver, intestine morphology, and serum parameters of overfed geese
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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Animal Production Science 57 (7)D. M. Weary, M. A. G. von Keyserlingk
Animal Production Science 57 (7)W. J. Wales, E. S. Kolver
Animal Production Science 57 (7)Jennie E. Pryce, Matthew J. Bell
Smallholder large ruminant health and production in Lao PDR: challenges and opportunities for improving domestic and regional beef supplyAnimal Production Science 57 (6)S. Nampanya, S. Khounsy, J. R. Young, V. Napasirth, R. D. Bush, P. A. Windsor
Revisiting summer infertility in the pig: could heat stress-induced sperm DNA damage negatively affect early embryo development?Animal Production Science (Online Early)Santiago T. Peña, Jr, Bruce Gummow, Anthony J. Parker, Damien B. B. P. Paris
Animal Production Science 57 (7)Pablo Gregorini, Juan J. Villalba, Pablo Chilibroste, Frederick D. Provenza
Animal Production Science (Online Early)J. P. Goopy, D. E. Pelster, A. Onyango, K. Marshall, M. Lukuyu
Animal Production Science 57 (7)C. D. Lewis, C. K. M. Ho, B. R. Cullen, B. Malcolm
Effect of replacing a commercial pelleted calf meal with lucerne leaf-meal on performance of neonatal and transitional Holstein heifer calvesAnimal Production Science (Online Early)Joyce L. Marumo, Florence V. Nherera-Chokuda, Jones W. Ng'ambi, Mukengela C. Muya
Single nucleotide polymorphisms associated with osteochondrosis dissecans in Warmblood horses at different stages of trainingAnimal Production Science 57 (4)D. Lewczuk, M. Hecold, A. Ruść, M. Frąszczak, A. Bereznowski, A. Korwin-Kossakowska, S. Kamiński, J. Szyda
Animal Production Science 57 (7)J. B. Garner, M. Douglas, S. R. O. Williams, W. J. Wales, L. C. Marett, K. DiGiacomo, B. J. Leury, B. J. Hayes
Animal Production Science 56 (12)Saad Gilani, Gordon S. Howarth, Soressa M. Kitessa, Rebecca E. A. Forder, Cuong D. Tran, Robert J. Hughes
Early detection of clinical mastitis from electrical conductivity data in an automatic milking systemAnimal Production Science 57 (7)Momena Khatun, Cameron E. F. Clark, Nicolas A. Lyons, Peter C. Thomson, Kendra L. Kerrisk, Sergio C. García
Animal Production Science 56 (11)J. L. Klotz, A. M. Nicol
Dry matter intake and feeding behaviour of grazing dairy cows offered a mixed ration with or without canola mealAnimal Production Science 57 (7)M. M. Wright, M. J. Auldist, E. Kennedy, N. Galvin, F. R. Dunshea, W. J. Wales
Herbage dry-matter yield and nitrogen concentration of grass, legume and herb species grown at different nitrogen-fertiliser rates under irrigationAnimal Production Science 57 (7)Kirsty Martin, Grant Edwards, Rachael Bryant, Miriam Hodge, Jim Moir, David Chapman, Keith Cameron
Animal Production Science 57 (6)J. M. Havlin, P. H. Robinson, J. E. Garrett
Perennial ryegrass breeding and the scaling issue: a review of system experiments investigating milk production and profit differences among cultivarsAnimal Production Science 57 (7)Stacey J. Hendriks, Daniel J. Donaghy, Lydia M. Cranston, Grant R. Edwards, David F. Chapman
Efficiency of rumen microbial protein synthesis in cattle grazing tropical pastures as estimated by a novel techniqueAnimal Production Science 57 (8)M. K. Bowen, D. P. Poppi, S. R. McLennan
Animal Production Science 57 (7)Ashleigh M. Wildridge, Sergio C. Garcia, Peter C. Thomson, Ellen C. Jongman, Cameron E.F. Clark, Kendra L. Kerrisk