Faecal worm egg count (WEC) is an important trait for breeding for host resistance to parasites in sheep. The aim of the present study was to investigate whether genetic parameters differed for WEC measured at weaning, post-weaning, yearling and hogget age stages. The results showed lower variation and heritability at younger ages, and genetic correlations across ages significantly lower than unity, indicating that breeders would benefit by recording WEC at two or more different ages.

The size and body condition of female livestock are closely linked to physiological maintenance and reproduction, which are critical for improving production efficiency. Therefore, it is important to investigate the effects of the traits selected by breeding programs on the size of mature cows in order to avoid animals of undesirable size. Direct selection for weight, height or body condition score at the mature stage should be more efficient in controlling the adult size of cows, compared with selection of yearling traits.

The successful application of somatic cell nuclear transfer (SCNT) to a broad variety of species requires an improvement in its efficiency. We have seen, especially during the past 5 years, several technical strategies for improving SCNT, including strategies based on histone modification, embryo aggregation and mitochondrial function. These strategies will ultimately allow the promotion of SCNT technology to practical purposes.

An accurate determination of feed intake starts with the amount of nutrients required by pre-laying hens to meet the desired bodyweight and body composition. In this study, the feed intake of pre-laying hens was estimated, accounting for maintenance, body and reproductive growth, and the desired feed intake was predicted. Thus, we expect this study will provide valuable information towards nutrient utilisation, allowing nutritionists to formulate feeds closer to pre-laying hen needs, reducing the impact on the environment.

The balance of omega-6 : omega-3 fatty acids is important for health and longevity rather than the absolute amount, therefore this study focused on evaluating the dietary supplementation of varying ratios of omega-6 : omega-3 fatty acids (25 : 1, 20 : 1, 15 : 1 and 10 : 1) on performance of sows and piglets. Reduction of the omega-6 : omega-3 fatty acid ratio in the diet did not affect reproductive performance but positively affected piglet performance.

The productive performance of beef cows is directly correlated with the nutritional level. This study aimed to evaluate the effect of increasing levels of prepartum and postpartum protein supplementation on nutrient intake, productive performance, and metabolic status of beef heifers on tropical pasture. The supply of protein supplement for beef heifers optimises forage intake and average daily gain before calving.

The determination of the nutritional energy requirements for bovines of different genetic groups and under different feeding conditions allows the appropriate adjustment of feed formulation for each animal category. Knowledge of the energy partition of the diet and methane production allows the development of appropriate nutritional strategies respecting the environment.

Increasing scrutiny in New Zealand over the impact of dairy farming on water quality has prompted research to investigate alternative feeds that will maintain milk production, while reducing urinary nitrogen (N) excretion. This experiment investigated the impact of substituting fresh pasture with up to 60% of the diet dry matter as fodder beet in late lactation and demonstrated that including fodder beet significantly reduced urinary N excretion, but above 40% of the diet, it decreased animal health.

Brassica crops are used to supply feed in times of seasonal shortage, or when pasture quality is low. However, to the best of our knowledge, there is little information about the fermentation characteristics of these forages in the rumen. The present study assessed the nutrient concentration, in vitro fermentation and in situ rumen degradation characteristics of Brassica rapa ssp. rapa L. (turnips) and Brassica napus ssp. biennis L. (forage rape). Turnip and forage rape showed different nutrient concentrations and fermented rapidly and extensively in the rumen; however, most of the differences that were observed in the nutrient concentrations and degradation kinetics did not result in differences in in vitro fermentation products.

Oilseed meal, a by-product of oil production, is a protein source incorporated into dairy and feedlot rations. The present study examined general and digestibility characteristics of protein in Australian produced oilseed meals for dairy cattle utilisation. Ruminal protein digestibility differed among oilseed types and oil-extraction techniques. Research findings highlighted an opportunity to improve the quality of Australian oilseed meals by refining conditions of oil-extraction technique. Monitoring of ruminal protein digestibility of oilseed meals may benefit future feed formulation for improved dairy cattle utilisation.

Due to its significant impact on anthropogenic greenhouse gases, there is ongoing interest in reducing methane production from ruminants. Nitrate has been shown to reduce methane, but can also be deadly if too much is consumed, and the present study showed that intake is self-regulated at safe levels. However, intake is so low as to be minimally effective in reducing ruminant greenhouse gases.

Livestock production in tropical regions is developed under extensive systems, where an important proportion of an animal’s diet comes from non-conventional sources of fodders. Lucerne is one of the main dietary forage in ruminant production because of its high quality; however, it is expensive. Enterolobium cyclocarpum is a tropical tree fodder that can be used to replace lucerne in ruminant’s diets. Therefore, its use contributes to sustainable animal production by using local resources.

Grazing vegetative wheat, barley and oats is a strategic and tactical option for crop and livestock farmers; however, metabolic disorders have been reported and many producers avoid grazing crops with reproducing ewes. This research aimed to investigate the mineral status in pregnant ewes grazing vegetative crops and measure the effectiveness of mineral supplements for improving mineral status. The calcium status of ewes grazing cereal crops in late pregnancy was improved by providing supplements and this may decrease the risk of metabolic disease.

The study investigated the use of porcine bile, as an emulsifier, in starter broiler diets. The bile powder was added at 0, 1.25, 2.5 and 5.0 g/kg to a high fat diet containing crude palm oil. A diet containing 5.0 g/kg lecithin served as a positive control and low fat diet as the negative control. The results showed that 2.5 g/kg porcine bile is appropriate for use in a high fat broiler starter diet. This demonstrated the potential of this by-product from pig production as a potential additive for poultry.

With the view of reducing the supplementation of antibiotics in poultry feeding, different attempts have been practiced to suggest other alternatives. Therefore, the present research was designed to explore the possible effects of a synbiotic, organic acids or their combination on the growing efficiency, carcass yields and haematological picture in broiler chickens. The dietary supplementation with a synbiotic or synbiotic plus organic acids can improve the growth performance, carcass traits and blood-related indices in broilers.

Space allowance is a key element for pig welfare in intensive farming systems. However, to determine the adequate space allocation for pigs kept in groups is difficult and current spatial requirements are mostly based on theoretical calculations. In the present study, an innovative computer-assisted measurement was performed so as to gain precise data on the amount of space that is needed by the pigs’ bodies kept in groups of eight. A first basis for assessment of current space recommendations is provided.

Hens using the outdoor range on free-range layer farms is beneficial to welfare as this can reduce injurious feather pecking and encourages a more natural repertoire of behaviours. The objective was to encourage as many hens as possible to utilise the range; the project achieved this on commercial farms by providing a highly enriched range with the addition of shelters, dust baths, hay and pecking objects. Our results can be readily adopted by commercial egg farmers due to simplicity and low cost of the structures used.

Slower growing Merino sheep often become yearlings, however may still produce meat of acceptable eating quality. Sensory differences of untrained consumers on Merino lamb versus yearling sheep were tested, and results demonstrated the better eating quality of lambs compared to yearlings but highlighted a very acceptable eating quality of the yearling loin. This opens the possibility of developing a high quality yearling product for this cut for Australian consumers.

Fatty acid (FA) profile of dairy bull beef from different production systems is an important issue on the end of milk quotas. Forage-fed beef had relatively better nutritional property, while nutritionally beneficial FA had a negative effect on palatability. There appears to be considerable scope to change FA of beef to make it more acceptable to consumers from both healthiness and taste perspectives.

Feeding tannin to lambs alters the ecosystem of ruminal microorganisms, impairing the ruminal biohydrogenation process and changing the fatty acid profile in the meat. We have added condensed tannin from dry tamarind residue to lamb diets and observed the effect on the carcass traits, quality and fatty acid profile of the lamb meat. On the basis of our results, adding tannin to lamb diets is recommended to improve the fatty acid profile of the meat by reducing saturated fatty acids (SFAs) and increasing polyunsaturated fatty acids (PUFAs), which may improve the health of consumers.

Selecting animals with adequate degree of finishing for slaughter can increase meat quality. However, the available technologies to in vivo measure subcutaneous fat thickness, such as ultrasonography, may not be accessible to most beef farms. As an alternative, by monitoring the degree of finishing on the farm using a simple method such as internal angle of the rump (IAR), farmers can potentially provide better carcasses for processing by the industry.