Clear, unbiased use and reporting of males and females in animal studies promotes novel and reproducible research findings. An analysis of how males and females are used in animal studies in CSIRO was undertaken to review and further support best practice. Future experimental planning should balance the expected size of a sex effect with the costs of adding both sexes to experiments, and precise details of the animals used should be reported.

Glycerin represents an alternative of reducing costs in broiler production. We evaluate whether glycerin interferes in the performance characteristics and in the expression of mitochondrial and antioxidant genes. Although the expression of UCP and GPx genes has been increased, we conclude that glycerin can be used as an alternative in poultry feed without lost performance.

Eggs with a much higher proportion of thick albumen are favoured by consumers. This study investigated the effect of strain and age on the ratio of thick-to-thin egg albumen and found that the selection for egg composition traits could be performed at 30 weeks of age with high accuracy. The results contribute to future breeding strategies that optimise the proportion of thick egg albumen.

With an accurate description of potential egg production, egg weight and its internal constituents (albumen, yolk, and shell), a simulation model to predict egg production and egg weight can be performed. Equations were developed to update the commercial layer genetic potential. This approach allows both improvement in egg production prediction and understanding of hen nutritional requirements.

The quails have high reproductive sensitivity at different light colours. Actually, LED (light-emitting diode) lamps are being increasingly used in the production system, mainly due to greater durability and power efficiency than those of other types of lamps. In our study, we concluded that the white LED resulted in better physiological and metabolic conditions of the birds than did other types of lamps, resulting in birds with a higher reproductive potential.

Because broiler breeder hens are allocated a restricted amount of feed each day, the nutritionist must calculate what daily allocation of energy would be sufficient for maintenance and egg production. The present research explored the effects of energy supply over a range of temperatures on egg production and body fat deposition in these hens. At low temperatures, when the energy supply is marginal, the hen reduces the rate of laying and increases fat deposition.

Genetic selection of low methane emitting sheep to reduce Australia’s greenhouse gas emissions must account for variation in methane production over an annual production cycle. Methane emissions by sheep increase as animal’s age and potentially decrease during pregnancy. The reasons for these changes are explored. Measurement of methane production to obtain genetic parameters is best when animals are not pregnant.

The study of vitamin D in cattle has often focussed on its role in calcium and mineral metabolism; however, there is evidence of a wider role for vitamin D in bone and energy metabolism. In the present study, feeding calcidiol had positive effects on vitamin D, mineral and energy metabolism in mid-lactation dairy cows. These experiments provide support for a positive effect of calcidiol treatment on dairy cow metabolism.

The ability to produce food of animal origin that promotes benefits for consumers and animals is a current challenge. Thus, the use of minerals in the diet of dairy sheep is an alternative and selenium (diphenyl diselenide) shows that its use can stimulate the animal immunity and elevate the antioxidant power of milk. The knowledge presented is evidence that animal health and good food go hand in hand.

The supplementation with fibrolytic enzymes (FE) could compensate for the inadequate endogenous enzymes in calves, increase feed fibre degradability and provide sufficient nutrients for ruminal bacteria which were promoted by isobutyrate (IB) supplementation. The combination of IB and FE has the potential to stimulate the growth of dairy calves during pre- and post-weaned period by increasing microbial enzyme activity and promoting the growth of cellulolytic bacteria.

Opuntia stricta (haw) haw: a new option for dairy cows in semiarid regions. Two varieties of spineless cactus are ingredients in the diet of lactating cows producing 20 kg/day of milk in areas infested with Dactylopius opuntia Cockerell. Resistant spineless cactus maintains the sustainability of production on milk farms in semiarid regions.

Brown-midrib corn silage (BMRCS) presents higher fibre digestibility than does conventional corn silage, which may allow greater animal intake and efficiency to enhance beef cattle production. In the current study, total dietary fibre digestibility was increased by the inclusion of BMRCS in a diet of finishing steers. While there was no significant improvement in animal performance, the carcass yield was enhanced. The present results show that further research is necessary to evaluate the potential of BMRCS as a tool in beef cattle production.

Grazing ewes on lucerne (alfalfa) crops that contain elevated coumestrol concentrations before and during the mating period can decrease their ovulation rate. This research showed the risk of impaired lambing performance decreased after removal from lucerne, and full recovery was predicted at 2 weeks for ewes that were removed from a moderately oestrogenic lucerne forage. These findings provide farmers with guidelines to increase confidence to feed lucerne to ewes closer to the onset of the mating period than has previously been considered safe.

Preserved forage is a major feed source for ruminants. This study aimed to investigate effects of silage type on nutrient utilisation efficiency and methane emission of dairy cows. In comparison with grass silage and maize silage diets, a whole crop wheat silage diet produced a lower methane loss per kg dry matter intake. The silage type has capacity to affect energy utilisation and methane emissions in dairy cows.

Wheat is a valuable energy source for lactating dairy cows, but if introduced into the diet rapidly it can adversely impact health and production. In this experiment cows previously consuming only lucerne hay cubes were rapidly introduced to large amounts of wheat, with no detrimental effects on intake or health. These results suggest an opportunity to tailor grain introduction strategies based on the properties of the accompanying forage, potentially saving dairy farmers time and avoiding major health issues for cows.

The present study showed that nitrate inclusion in the diet has the potential to improve fermentation in sheep, reducing gas production measured by in vitro technique. Nitrate had no effect on dry-matter degradation, an important factor of livestock yields. Also, these results suggested that there is a meaningful relationship between in vitro and in situ methods.

It is necessary to accurately evaluate the effective energy in different types of sorghum grain to formulate diets economically and effectively. The effective energy of low-tannin white and high-tannin red sorghum was compared, and low-tannin white sorghum contains more effective energy than high-tannin red sorghum. Therefore, less supplemental energy will be needed when diets are formulated for pigs based on low-tannin white than high-tannin red sorghum varieties.

Consumer demand for healthier and better quality foods is increasing worldwide and, consequently, swine has undergone intense genetic modification to produce animals with a leaner and healthier carcass. Furthermore, investigators have been studying the benefits of ractopamine on finishing-pig diets due to its effectiveness in promoting lean meat deposition. In the present study, ractopamine inclusion improved average weight gain, feed to gain efficiency, and lean meat deposition without compromising meat quality.

Lamb survival in Merino ewes, especially those bearing twins, can be very low leading to reduced production and animal-welfare concerns. The present study investigated whether providing barley grain in late gestation can improve lamb survival when pasture availability is high. Supplementation did not increase lamb survival and is not a recommended strategy where ample quality pasture is available throughout lambing.

In the South Island high country of New Zealand large tracts of native-tussock grasslands are increasingly being used for red deer farming. The present study used GPS-tracking and GIS technologies to identify the main habitats that red deer use in these tussock-grasslands, the typically daily behavioural patterns of the deer, and the likely long-term consequences of their behaviour on this type of grassland ecosystem. The results of the present study will aid in the future management of this type of grassland under deer farming.

Calves are routinely castrated however this procedure is commonly performed without pain relief. There is a need to evaluate pain mitigation strategies for ring castration of calves, which are practical for farmers to administer, such as a buccal formulation of meloxicam. Buccal administration of meloxicam immediately before ring castration of calves appeared to have no alleviating effects on the acute pain response to this procedure, however further investigation into timing of drug administration is warranted.

Milking cows once daily (OAD) is one solution to labour problems in the New Zealand dairy industry. Comparison between 302 commercial herds milking OAD and 2424 paired herds milking twice-a-day (TAD) indicated improved reproductive performance, a change in reasons for cows exiting the herd, and the use of fewer Holstein–Friesians in OAD herds. However, a decrease in milk production of ~11% was experienced in the first season, which was not recouped relative to TAD herds. Farmers considering OAD should evaluate the trade-off between the ability to decrease costs to offset decreased production and impacts on labour and/or lifestyle.

Feed waste represents a considerable expense for pork producers. We aimed to quantify in-shed feed waste by measuring the acidity of effluent across two pig farms. We found that increasing feed waste in shed corresponded to increasingly acidic effluent. Hence, monitoring effluent pH could be a simple approach to alert farmers to potential feed waste issues thereby minimising production costs.

Sustainability of ruminant production systems has raised much interest in recent years. Feedlot lambs were fed concentrates rich in fibrous by-products and other unconventional ingredients, as alternatives to cereal and soybean meal, and no negative effects on performance as well as carcass and meat quality traits were found. A by-product-rich concentrate can cost-effectively replace traditional feeds for lambs, avoiding competition for feed with swine and poultry.