Animal Production Science
Volume 57 Number 10 2017
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
AN15551Equid milk production: evaluation of Martina Franca jennies and IHDH mares by Wood’s model application
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.
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.
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.
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.
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.
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.
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.
The peer-reviewed and edited version of record published online before inclusion in an issue
AN17335Effects of common dietary fatty acids on milk yield and concentrations of fat and fatty acids in dairy cattle
Milk fat consists of different classes of fat, namely, shorter saturated fatty acids made in the mammary gland and longer fatty acids derived from the diet. Dietary unsaturated fatty acids fed to cows can decrease secretion of the former and supply more of the latter. Measurement of these fat classes in milk on a routine basis is now possible, allowing better diagnosis of feeding problems and better control of milk fat composition.
Beef cattle in northern Australia often eat pastures that contain low amounts of phosphorus, a mineral that is required for normal growth. In this paper, we propose new markers in blood that can be tested to determine whether cattle lack phosphorus in their diet. These markers could help farmers make more informed decisions about whether they need to provide phosphorus as a diet supplement to their breeding cows.
AN17389Calcium and phosphorus metabolism and nutrition of poultry: are current diets formulated in excess?
In the present review, recent advances in the understanding of Ca and P metabolism and poultry nutrition are described. Recent data are provided in support of the proposition that current poultry diets are formulated in excess for Ca and P. The challenge in applying a lower dietary Ca and P strategy commercially is uncertainty about the appropriate dietary concentrations of bioavailable Ca and P. These should be determined by applying the direct ileal or pre-caecal approach for determining Ca and P digestibility.
The global demand for protein is increasing and animal-based proteins are facing increasing competition from other protein sources. Artificial meat and meat substitutes such as plant, fungal, algal or insect proteins may have an enhanced capacity to respond to different market demands when compared with conventional meat production. The future of meat and protein will likely comprise a combination of conventional meat, meat substitutes and synthetic meat products, all serving different segments of the market.
AN16147Quality characteristics of meat from triceps brachii muscle from steers and heifers finished on high-concentrate diets containing increasing concentrations of linseed oil
High concentrate diets with increasing linseed oil concentration were offered to steers and heifers to evaluate quality traits of meat. The higher linseed oil concentration increased the levels of important fatty acids such as n-6 and n-3. The inclusion of linseed oil is a strategy to produce meat with benefits for human health.
This study evaluated the effect of freezing (−18°C) for 12 months on the qualitative characteristics of breast, thigh and drumstick meat from antibiotic-free, conventional, organic and free-range broilers. Freezing chicken meat did not prevent colour and pH changes or occurrence of lipid oxidation and did not promote a reduction of aw to levels unfavourable to microbiological development.
AN14583Divergent 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
Angus heifers with extreme estimated breeding values (EBVs) in rib fat depth (Fat) or post-weaning residual feed intake (RFI) were evaluated for their pregnancy rates. High-fat heifers had a greater pregnancy rate than Low-fat heifers. Pre-joining weight was the strongest determinant of likelihood of conception and pre-joining fat depth was also important. As expected, the days to calving EBV was the best EBV predictor of pregnancy success.
AN17382Biofilm compartmentalisation of the rumen microbiome: modification of fermentation and degradation of dietary toxins
The majority of rumen bacteria are found in biofilms attached to particulate matter in digesta. These biofilms provide organised habitats for diverse but inter-dependent microbial communities that play crucial roles in feed organic-matter fermentation and in detoxification of dietary toxins. Inclusion of materials such as biochar, bentonite or charcoal in the diet, which markedly increase the surface area for biofilm attachment, may provide additional niches for the development of specific microbial consortia that can degrade potentially toxic dietary materials and, thereby, protect the host animal.
Consumption of lamb meat has decreased considerably, in addition to preference for first class pieces only. In order to increase carcass value and consumption, lamb burgers were prepared from different parts of the carcass and spices. The results showed that the manufacture of these meat products could optimise the value of lamb carcass.
AN17324Utilising mobilisation of body reserves to improve the management of phosphorus nutrition of breeder cows
In breeder herds grazing phosphorus-deficient rangelands reproduction may be severely reduced by dietary deficiencies of phosphorus. The substantial body reserves of phosphorus, particularly in the skeleton, may be mobilised during pregnancy and lactation to alleviate the consequences of inadequate diet phosphorus. However, to avoid longer-term adverse effects body phosphorus reserves must be replenished later in the annual cycle.
AN16804Efficacy of antioxidant and antimicrobial activity of whole porcine blood hydrolysates and its fractions under in-vitro conditions
Natural food preservatives derived from blood can be an alternative for artificial additives widely used in food and the pharmaceutical industry. Hydrolysates obtained by enzymatic hydrolysis of porcine blood were assessed for their antioxidant and antimicrobial efficacy. The study revealed that porcine blood hydrolysate (whole and fractions) can be a potential source of natural preservatives for shelf-life extension in food.
AN14594Divergent breeding values for fatness or residual feed intake in Angus cattle. 6. Dam-line impacts on steer carcass compliance
This paper is on the progeny of cows in the Maternal Productivity trial. It has been clearly demonstrated that for grass finished carcasses, progeny of Low-Fat cows failed to reach market specifications. The implications of this are discussed.
ASKBILL is a web-based program that provides accurate forecasts to help producers better manage sheep well-being and productivity. The program uses biophysical models, customised by user inputs, localised daily weather updates and 90-day climate forecasts. The predictive functionality will be particularly useful in managing risks and production opportunities that involve the interaction of nutritional status and climatic or parasite events.
Australian seedstock cattle breeders have expressed concerns that while there has been genetic improvement in feedlot and abattoir performance of cows, it could have led to a decline in maternal productivity, especially under variable nutritional conditions. This paper describes a substantial project with two components designed to address these issues.
AN17343Procedures for determining digestibility of amino acids, lipids, starch, fibre, phosphorus, and calcium in feed ingredients fed to pigs
Diets for pigs need to be formulated based on concentrations of digestible nutrients. Digestibility of amino acids, lipids, and starch is determined at the end of the small intestine and is known as ‘ileal digestibility’, but digestibility of minerals and fibre is determined as ‘total tract digestibility’. Corrections for basal endogenous losses of nutrients are necessary to obtain values that are additive in mixed diets, and values for the standardised ileal digestibility or the standardised total tract digestibility are calculated.
Feed is the single largest cost in animal production. The purpose of this review is to examine evidence for the role of the mitochondria in helping to drive variation in feed efficiency between individuals, breeds and species. There is some evidence that mitochondrial content and certain aspects of mitochondrial physiology, particularly in muscle tissue, are associated with high feed efficiency.
Omeprazole is commonly provided to horses to treat and prevent gastric ulcers but there is concern regarding whether it may impair mineral absorption and, thus, bone health. This study compared mineral balance and bone health parameters in five treated and five control horses. No meaningful treatment differences were seen, minimising concerns of preventative treatment for up to 2 months.
The modern diet formulation of domestic animals relies almost exclusively on the use of computer models that are developed based on our scientific knowledge of animal nutrition and management. Recent data analyses using larger datasets and advanced statistical methods suggest that some improvements are needed. However, animal nutritionists, specifically ruminant (e.g. cattle, sheep, and goats) nutritionists, must rethink old concepts and relationships before spending more resources on collecting additional data.
The administration of antimicrobials to poultry for growth promotion has been linked to the global health crisis of antimicrobial resistance, resulting in consumer demand for products free of antimicrobial residues. This review discusses developments in alternatives to antimicrobials for managing gut health. The findings highlight the potential for using in-feed nutraceuticals, such as probiotics and prebiotics, as alternatives to antimicrobials, to create a healthy gastrointestinal environment and prevent and treat intestinal diseases.
AN16784Feeding wet distillers grains plus solubles contributes to sarcoplasmic reticulum membrane instability
Past studies have shown that beef from cattle fed a high concentration of distillers grains was more tender than beef from cattle fed corn only. To understand why, this research characterised the muscle and lipid properties of meat from the different diets. Results suggested feeding distillers grains may increase tenderness, possibly by altering sarcoplasmic reticulum membrane integrity, resulting in more rapid intracellular calcium leakage to enhance the meat aging process.
Growth, health and production performances of progeny can differ depending on their maternal environment such as sow parity number. This study aimed to identify the influence of sow parity on the meat quality of progeny. We identified that maternal parity may affect pork quality in progeny and the younger stage group could have better meat quality than the older group.
AN17058Segmentation of Australian meat consumers on the basis of attitudes regarding farm animal welfare and the environmental impact of meat production
Public concern over farm animal welfare (FAW) in the livestock sector is believed to be increasing. The present study is the first nationally representative study of Australian meat consumers to identify consumer segments with distinct attitudes towards FAW and the environmental impact of meat production. The majority of consumers (70%) are unconcerned about FAW, and most admit to feeling insufficiently informed about FAW. Targeted information and marketing campaigns may enable more informed meat-purchase decisions.
AN17174Effect of individual Ayurveda plants and mixtures thereof on in vitro ruminal fermentation, methane production and nutrient degradability
Great efforts have been made to identify nutritional ways to mitigate emissions of the greenhouse gas methane from ruminants. Several medicinal plants containing specific plant secondary metabolites were screened as sole substrates and as supplements, individually as well as in binary combinations. Combining A. paniculata and P. longum mitigated methane without side effects on ruminal fermentation. In vivo experiments yet to be conducted will show whether this combination has the potential to be developed as feed additive for ruminant nutrition.
AN17057Effect of nano-selenium and nano-zinc particles during in vitro maturation on the developmental competence of bovine oocytes
The present study evaluated the effects of supplemental nano-selenium (NSe) and nano-zinc oxide (NZn-O) particles during in vitro maturation (IVM) on DNA damage of cumulus cells, glutathione concentration in bovine oocytes, subsequent embryo development and the re-expansion rate of vitrified warmed blastocysts. Optimal embryo development was partially dependent on the presence of NSe and NZn-O during IVM. NSe and NZn-O during oocyte maturation act as good cryoprotective agents of vitrified, warmed blastocysts.
AN17055Recombinant bovine somatotropin on heifer’s biometric measures, bodyweight, blood metabolites, and dry matter intake predictions
Strategies to accelerate growth of heifers decrease time until the productive period. This study evaluated whether sustained-release recombinant bovine somatotropin injections increase the growth rate of replacement dairy heifers. Recombinant bovine somatotropin increased bodyweight gain and skeletal growth, suggesting that heifers would reach puberty and productive life earlier, decreasing the energy waste related to methane and urine outputs into the environment.
AN16812Growth performance and carcass characteristics of Australian prime lambs supplemented with pellets containing canola oil or flaxseed oil
Can growth and carcass traits be enhanced in prime lambs using omega-3 oil supplements? Crossbreds had better carcass weight, dressing percentage and fat depth than purebred Merinos. Prime lamb producers can better match genetics with feed resources by supplementing first-cross lambs with pellets containing 5% canola oil or 5% flaxseed oil pellets in an intensive finishing period of 10 weeks.
The utilisation of pasture as a predominant source of nutrition for broodmares and young stock is a unique feature of the New Zealand commercial equine industry. The export focus of the Thoroughbred industry has a large influence on many husbandry practices and industry structure.
Community concerns about animal welfare can shape livestock practices and may affect the sustainability of livestock industries by compromising their social licence to farm. The results reported here show that attitudes towards the livestock industries predict engagement in community behaviours that express dissatisfaction with the way livestock animals are treated (such as petition signing) and, to a lesser extent, pork consumption. Further research to characterise and engage opinion leaders involved in many community behaviours relevant to the livestock industries is needed as a possible way of establishing convergence in beliefs between producers and the community.
It is common to identify stress responses by measuring various hormones and to conclude that stress affects the welfare of animals. The reality is that there is not always a straightforward relationship between stress, hormones and animal welfare. We need to know the consequences of the actions of hormones in order to assess how stress affects animal welfare.
Pigs are fed mainly with cereals as energy sources, and fats and oils, due to their high energy content, represent an attractive ingredient. Nonetheless, fats are usually more expensive than cereals and high levels in the diet are not well tolerated by pigs. In this study, we tested the use of a crystallised powdered oil mix produced by a technology process and included at levels close to 10% and this resulted in improved digestion efficiency and in a better growth performance in pigs.
Breeding mares are kept at pasture in New Zealand and reproductive efficiency is improving. However, Thoroughbred breeders face significant pressures from industry with a short breeding season that does not match the timing of the natural breeding season, and popular stallions are required to breed many mares. Breeding horses require excellent stud management and veterinary management to achieve industry targets.
AN17048Genotype by environment interaction for yearling weight in Nellore cattle applying reaction norms models
Selection of production animals may be compromised when there is no knowledge of the relationships between genotype and the environment in which a particular animal is inserted. This work aimed to investigate the impact of the genotype environment interaction on the performance of cows in the postweaning phase. It was verified that in Nellore individuals there was no significant impact of the environment on the genotype of the animals, concluding that the same selection criteria can be adopted between the mentioned regions in the studied regions.
Phytases release phosphorus and other minerals as well as energy and amino acids from the undigestible fractions of monogastric diets. However, their ability to perform this function is severely compromised if the concentrations of dietary calcium are higher than expected, and this is a frequent occurrence in commercial diets. Given the value of phytases now extends very much into amino acid nutrition as well as mineral, it is even more important to monitor and avoid excess calcium if resource optimisation is to be achieved.
The use of agribusiness co-products as replacers of other cereal grains can decrease costs on cattle feed. The aim of this work was to study the feasibility of replaced soybean meal by sunflower cake (up to 60%) in heifers finished on pasture. The qualitative and sensory characteristics of meat were not altered, proving the viability of this kind of feed replacement.
AN16292The effect of lipid metabolism-related genes on intramuscular fat content and fatty acid composition in multiple muscles
Intramuscular fat and fatty acid composition significantly affect meat quality, but the regulation mechanism of lipid metabolism among multiple muscles is unclear. Here, we found seven genes associated with lipid deposition in muscle tissues, and identified the relationship between muscle fibre types and monounsaturated fatty acids/saturated fatty acids. These results added beneficial information to improve meat quality, and provided potential genetic markers for the study of fatty acid composition.
The lining of the gastrointestinal tract is the body’s largest and most vulnerable external surface. To optimise the digestion and absorption of nutrients and to defend against pathogens and toxins, the lining has an extensive repertoire of sensory mechanisms. These signal to the gut endocrine system, the nervous system, the immune system and local defence in order that digestive efficiency and gut health are optimum.
AN16375Differences on meat colour and composition between ‘Landrace × Large White’ and ‘Iberian’ pigs under identical nutritional and management conditions
Composition and colour of porcine meat are strongly involved in meat quality and may be affected by the nutritional management and the genotype of the animals. In this paper, we show that, even under identical nutritional treatments, significant differences exist on composition, mineral content, fatty acid profile and colour of meat between Iberian and lean pigs, at different growing stages. Characteristics such as the high amount of intramuscular fat, the great concentration of heme pigments and the high level of monounsaturated fatty acids are among the more relevant quality aspects of Iberian muscles.
AN16184Comparison and relationship between meat colour and antioxidant capacity of different pig breeds
Comparative study between Chinese native pig breeds and commercial crossbred pigs can provide information on meat colour and antioxidant capacity of different breeds. This is a preliminary study on antioxidant capacity in Chinese native pig breeds, exhibiting higher antioxidant capacity than commercial crossbred pig. This discovery could provide a new perspective on meat colour and antioxidant capacity, and these results implied that there was a strong relationship between meat colour and antioxidant capacity.
AN16242Effect of the inclusion of natural additives on animal performance and meat quality of crossbred bulls (Angus × Nellore) finished in feedlot
Natural additives can modulate ruminal fermentation on high energetic density diets. The aim of this work was to study the effect of essential oils and yeast inclusion on cattle diets. Addition of natural compounds (oregano, castor bean, cashew oils and yeast) improved bull performance, without changing significantly meat characteristics. Natural additives could be an alternative for ionophores substitution.
AN16573A non-synonymous single nucleotide polymorphism in the paraoxonase 3 gene regulates meat quality in Berkshire pigs
The paper is about the selection method for high-quality pork. In the research, the investigators identified genetic markers that regulate meat quality in Berkshire pigs. These meat quality-associated markers can be applied to pig breeding to produce high-quality pork.
AN16223Comparisons of meat quality and muscle fibre characteristics on multiple pig breeds and sexes using principal component analysis
Comprehensive understanding of the effect of pig breed and sex on meat quality and post-mortem muscle conditions will be necessary to estimate post-mortem meat quality. Here, we applied multiple regression and principal component analysis on multiple breeds and sexes. We observed that muscle pH, lightness, and drip loss are useful for estimating ultimate pork quality.
AN16730Herd dynamics reflect constraints for pig production and farmer attitudes in smallholder systems in Lao PDR
Pig production is a common activity of smallholder farmers in Lao PDR but its degree of sophistication is low, leading to missed opportunities in generating income. We found a lack of understanding for focussed production reflected in village pig herd dynamics, underlining problematic management practices that lead to high losses and poor performance. Future development interventions are encouraged to take the indicated reasons for such practices into consideration to improve their chances of sustainable impact.
This review presents data on the size, scope and organisation of equestrian sport and racing within New Zealand. The keys features of which are shaped by pasture-based management and a large export focus for the Thoroughbred industry. Describing the racing and sport-horse industries is essential to aid understanding of the production process of the equine athlete in New Zealand.
AN16354Evaluation of repeatability and pre-structured repeatability models for genetic analyses of repeated records of fat and protein contents of milk in Iranian Holstein cows
In an animal breeding program, selection accuracy can be increased using appropriate genetic model analysis. In the present study, a repeatability model will be developed. Accordingly, efficiency of animal improvement can be increased.
Addition of calcium oxide (CaO) can improve the intake and digestibility of sugarcane silage in beef cattle. The objective of this study was to examine the nutritional parameters of feedlot beef heifers fed with corn silage, fresh sugarcane or ensiled sugarcane with different CaO levels. Corn silages diets provide better nutritional parameters than sugarcane diets. Adding CaO to sugarcane silage provides greater intake than silage without CaO. However, the use of high levels of CaO decreases the diet intake.
AN17296Starch and protein digestive dynamics in low-protein diets supplemented with crystalline amino acids
Low-protein diet containing high levels of synthetic amino acids is desirable to improve feed conversion and protein utilisation. Previous studies suggested that feed conversion efficiency may be enhanced by rapidly digestible protein. This review considers the importance of digestive dynamics of starch and protein, protein-bound and crystalline amino acids to develop strategies for low-protein diets in poultry.
AN15562Supplementation with N-carbamylglutamate and vitamin C: improving gestation and lactation outcomes in sows under heat stress
During summer, heat stress often causes sow reproductive failure. In later pregnancy and lactation, sows are under multiple heat stress; dietary supplementation with N-carbamylglutamate and vitamin C can improve reproductive performance of sows by increasing litter and average weights at farrowing and weanning. Our results can be used to ameliorate heat stress in summer and keep year-round pig production.
AN16563Genetic association between stayability, and productive and reproductive traits in Holstein cows
An important trait is the length of the productive life of a cow in the herd, or stayability. Here we estimate genetic merit of Brazilian Holstein cows and correlations of stayability with other measures of performance. We show low heritabilities for stayability but positive genetic correlations with milk production, suggesting that animals can be selected for both stayability and milk production in this population.
AN17051Variability of the IGF2 locus in the Suino Nero Lucano pig population and its effects on meat quality
The Insulin-like Growth Factor 2 gene (IGF2) is known as an important regulator of growth, development and differentiation of skeletal muscle. In this study, the polymorphism of the IGF2 gene and the effect of IGF2 genotypes on the quality of meat from Italian autochthonous Suino Nero Lucano breed were investigated. IGF2 genotypes were associated with different effects on both muscle mass and meat quality characteristics. As a consequence, in the SNL population it is possible to choose sires and dams according to the destination of the final product.
AN16823Effects of hydrated sodium calcium aluminosilicate on growth performance, fatty liver, intestine morphology, and serum parameters of overfed geese
As a worldwide-known delicacy, fatty goose liver (foie gras) is obtained from overfed geese; however, two factors could affect its safety and quality, excessive amounts of diet and antibiotics in feed. To solve this problem, we added hydrated sodium calcium aluminosilicate (HSCAS) into the diet and the results showed that HSCAS increased relative liver weight, serum immunoglobulin levels, and improved intestine morphology of overfed geese. HSCAS might serve as an alternative to increase nutrient absorption and replace antibiotics in foie gras production.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
The impact of two different hormonal growth promotants (HGPs) on the eating quality of feedlot finished steer carcasses.
Do varied dietary omega-6: omega: 3 ratios impact the performance, nutrient digestibility, immune status and faecal microbiota of weaner pigs
Sheep and goat browsing a tropical deciduous forest during the rainy season: why does similar plant species consumption results in different nutrient intake?
Histomorphometric analysis of the effect of in ovo injected methionine on small intestine in broiler chicken embryo
Effect of shade access combined with or without sprinkling and ventilation on performance of Holstein cows in two lactation stages.
The effectiveness of using energy preparations in feed rations for cows in the periparturient period
Effect of pelleted total mixed rations with different levels of intact rapeseed on performance, carcass traits, serum biochemical indices and meat quality of Boer goats
Effects of immunocastration on the performance and meat quality traits of feedlot-finished Bos indicus (Nellore) cattle
Effect of quality control, density and allele frequency of markers on the accuracy of genomic prediction for complex traits in Nellore cattle
The effect of a probiotic preparation containing Enterococcus faecium DSM 7134 for chickens on growth performance, immune status, and the histology and microbiological profile of the jejunum
Quantification of methane emission in Murrah buffaloes fed different energy diet at varying temperature humidity index period in tropical environment
Predicting the nutritional quality of feed ingredients for pigs using near infra-red spectroscopy (NIRS) and chemical analysis
Off to the right start – how pregnancy and early life can determine future animal health and production
Keeping it “inside the fence”: An examination of responses to a farm animal welfare issue on Twitter
Comparative effects of powder, aqueous, and methanolic extracts of purslane (Portulaca oleracea L.) on growth performance, antioxidant status, abdominal fat deposition, and plasma lipids in broiler chickens
Influence of feed ingredients with pellet binding property on physical pellet quality, growth performance, carcass characteristics and nutrient retention in broiler chickens
Physicochemical and Sensory Characteristics of Dry-cured Loin made from Pigs fed Allium Hookeri added Whey Powder and Sensory Trait Evaluation using Electronic Tongue
Weaner Survival is Heritable in Australian Merinos and current breeding objectives are potentially leading to a declines in survival
Using highly nutritious pastures to mitigate enteric methane emissions from cattle grazing systems in South America
Physicochemical properties of horse meat as affected by breed, sex, age, muscle type and ageing period
Inoculant effects on the fermentation quality, chemical composition and saponin content of alfalfa silage in mixture with wheat bran or corn husk
The effects of substituting 50% of dietary soybean with urea or a slow-release urea on finishing performance, meat quality, and digestion parameters of Nellore steers
The effect of fasting on the appetite-associated factors and energy sensors expression in the hypothalamus of different TI broilers
In vitro acidification potential and fermentation pattern of cereal grains incubated with inoculum of ruminants given forage or concentrate based diets
Effect of the acute heat stress on serum endotoxin concentration and the expression of TLR4 mRNA in liver of Arbor Acres broiler chickens
Novel bioactives and management strategies to stimulate gut health and performance in post weaned pigs.
Effects of different road conditions on rectal temperature, behaviour and traumatic injuries during transportation of different crosses of temperate/tropical breeds of heifers
The effects of dry or wet aging on the quality of the longissimus muscle from 4-year-old Hanwoo cows and 28-month-old Hanwoo steers
Effects of tonic immobility (TI) and corticosterone (CORT) on mitochondria metabolism in pectoralis major muscle of broiler chickens
Effects of forage type and age at which forage provision is started on growth performance, rumen fermentation, blood metabolites and intestinal enzymes in Holstein calves
Carcass lean-yield effects on the fatty acid and amino acid composition of Duroc pork and its technological quality after vacuum-ageing
Performance, hepatic function and efficiency of nutrient utilization of grazing dairy cows supplemented with alkaline-treated Jatropha Curcas L. meal
Maternal body composition in seedstock herds: 5. Multivariate analysis using factor analytic models and cluster analysis
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
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
The Most Read ranking is based on the number of downloads in the last 60 days from papers published on the CSIRO PUBLISHING website within the last 12 months. Usage statistics are updated daily.
Animal Production Science 57 (7)W. J. Wales, E. S. Kolver
Animal Production Science 57 (7)D. M. Weary, M. A. G. von Keyserlingk
Animal Production Science 57 (7)Jennie E. Pryce, Matthew J. Bell
Feeding wet distillers grains plus solubles contributes to sarcoplasmic reticulum membrane instabilityAnimal Production Science (Online Early)M. D. Chao, K. I. Domenech-Perez, L. S. Senaratne-Lenagala, C. R. Calkins
Animal Production Science 57 (9)D. L. Michalk, W. B. Badgery, D. R. Kemp
Consequences of genetic selection for environmental impact traits on economically important traits in dairy cowsAnimal Production Science (Online Early)Purna Kandel, Sylvie Vanderick, Marie-Laure Vanrobays, Hélène Soyeurt, Nicolas Gengler
Animal Production Science (Online Early)J. P. Goopy, D. E. Pelster, A. Onyango, K. Marshall, M. Lukuyu
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
Herd dynamics reflect constraints for pig production and farmer attitudes in smallholder systems in Lao PDRAnimal Production Science (Online Early)Tassilo T. Tiemann, Ammaly Phengvilaysouk, Soukanh Keonouchanh
Designing a grazing-system experiment for variable native pastures and flexible lamb-production systemsAnimal Production Science 57 (9)W. B. Badgery, D. Mitchell, G. D. Millar, K. Broadfoot, D. L. Michalk, P. Cranney, W. Brown
Animal Production Science 57 (9)Felicity Cox, Warwick B. Badgery, David R. Kemp, Gaye Krebs
Animal Production Science (Online Early)Don Menzies, Kym P. Patison, Nick J. Corbet, Dave L. Swain
Animal Production Science (Online Early)Erica K. Gee, Chris W. Rogers, Charlotte F. Bolwell
Animal Production Science 57 (9)D. C. Mitchell, W. B. Badgery, P. Cranney, K. Broadfoot, S. Priest, D. Pickering
Animal Production Science 57 (9)W. B. Badgery, G. D. Millar, K. Broadfoot, D. L. Michalk, P. Cranney, D. Mitchell, R. van de Ven
Animal Production Science (Online Early)Charlotte F. Bolwell, Chris W. Rogers, Erica K. Gee, Sarah M. Rosanowski
Assessing the profitability of native pasture grazing systems: a stochastic whole-farm modelling approachAnimal Production Science 57 (9)Martin R. Amidy, Karl Behrendt, Warwick B. Badgery
Animal Production Science 57 (7)P. J. M. Raedts, S. C. Garcia, D. F. Chapman, G. R. Edwards, N. Lane, R. P. Rawnsley
Post-experimental modelling of grazing systems to improve profit and environmental outcomes using AusFarmAnimal Production Science 57 (9)K. M. Broadfoot, W. B. Badgery, G. D. Millar
Animal Production Science 57 (9)W. B. Badgery, G. D. Millar, D. L. Michalk, P. Cranney, K. Broadfoot