Residual feed intake is a relevant trait for beef cattle, given the positive impact on reducing feeding costs and greenhouse gas emissions. The study of genetic parameters for this trait is required, with the aim to be included into breeding programs. As the availability of large databases for this trait is limited, we study the performance of two sources of data, evaluating if they are possible to be pooled to estimate more accurate genetic parameters.

In vitro embryo production expanded in the past decade, as a result of the progressive adoption of this technique as a choice for embryo production, mainly in zebu breeds. Studies about embryo production are needed for its better exploration in animal breeding programs. We found that the number of oocytes obtained by follicular aspiration can be used as a trait to select better donors for embryo in vitro production. Our results may contribute to improve Gir dairy cattle reproductive performance.

During the dry season (early autumn-late spring) in subtropical semi-extensive management systems, food availability decreases markedly, leading to undernutrition of male goats. We demonstrate that this undernutrition reduces sexual behaviour and sperm production during the breeding season (early summer–late autumn). This study indicates that nutritional supplementation may improve the sexual activity of male goats kept under semi-extensive management.

Cattle in outdoor feedlots are candidates for heat stress. We evaluated the shade effect in steers during finishing under humid subtropical climate. Shade access increased feeding and ruminating time, daily dry-matter intake, average daily gain, feed:gain ratio and carcass weight, and decreased inactive time, respiration rate and panting. Shade improves steers performance, behaviour, and physiology in a region with an average THI from 70 to 72.

Supplementation is a nutritional strategy adopted to improve the performance of grazing cattle; however, there is still a lack of information on the best supplementation plan for heifers. Our main findings showed that although supplementation in the pre-weaning phase improves performance and nutrient intake, an inadequate nutritional plan during the post-weaning can substantially reduce the benefit of the additional gains made during the pre-weaning phase. This shows the importance of maintaining high weight gains at all stages of growth.

The search for foods that can replace the corn in feed without compromising the performance of the animals, has been the object of study by many researchers. Brown rice bran presents as antinutritional factors, high levels of crude fibre and phytic phosphorus, which result in low nutritional availability. However, addition of exogenous enzymes, a product of the development of the food-additives industry, can be an effective way to optimise the use of this type of food.