This experiment aimed to investigate the genetic effect on production traits of reciprocal crossbred Thai native black-bone chickens. Some of the studied traits were mainly affected by genetic parameters and were genetically correlated with the others. The results demonstrated that these traits could be genetically inherited and improved, along with other traits.

The Morada Nova breed is an important animal genetic resource created by sheep farmers in the Brazilian semi-arid region. This breed has three genotypes: white, black and red. Our investigation sought to understand the thermoregulatory, acid–base and electrolytic dynamics of these genotypes according to the time of the day (morning, noon and end of the day) in the rainy and dry periods. All genotypes were able to return to homeothermy at the end of the day, regardless of the period

In sheep extensive production systems, pasture availability decreases in winter; thus, ewes are undernourished during gestation. Maternal melatonin treatment could mitigate intrauterine growth restriction induced by maternal undernutrition, enhancing bodyweight at birth and body temperature of lambs, and improving ewe–lamb behaviours at birth. In this study, only lamb hip surface temperature was enhanced after birth, whereas ewe–lamb interactions, lamb birthweight and rectal temperature were unaffected by melatonin treatment.

Manipulation of milk composition in lactating ewes has potential to increase profits from milk prices, cheese making and lamb growth. A practical choice to achieve this target is melatonin implantation, which is commonly used for alleviating reproductive seasonality outside of the breeding season. Melatonin implantation increased IGF-1 concentration, which contributed with melatonin to increasing milk components including fat, protein, lactose and total solids and milk energy value.

Eugenol is a bioactive compound with defined attributes, including a role in reducing oxidative stress, being an interesting candidate for in vitro embryo production in cattle. We demonstrated that a lower concentration of eugenol (83 μM) was sufficient to generate a significant effect, attenuating the oxidative status and optimising in vitro maturation. Therefore, this study provided information of a new natural antioxidant, eugenol, representing a lower cost alternative capable of improving the efficiency of in vitro embryo production in cattle.

The use of buserelin (GnRH agonist) can improve semen quality; nevertheless, the dosage, and frequency and time of application, are unresolved owing to the reported subsequent negative feedback on endogenous production of testosterone. In this study, the administration of buserelin improved some sperm kinetics parameters of Santa Inês rams. Therefore, low doses of buserelin can be used, although further adjustments to the hormonal protocol are needed to obtain an effective improvement in sperm quality.

The severity of nutritional restriction in beef cattle during the last trimester of gestation could affect fetal and postnatal growth and the physiology of the progeny. Maternal nutritional restriction in late gestation decreased the birth weight of offspring; however, severe restriction induced early postnatal compensatory growth. Events in fetal life play an important role in alterations of fetal organogenesis in response to maternal and fetal nutrition. These adaptations could permanently alter metabolism and manifestations throughout your life.

The use of breed crosses is an alternative for increasing animal production. For this purpose, breeds such as the Aberdeen Angus are already widely used, while Canchim animals present themselves as a viable alternative. Crossbred animals have better carcass characteristics and initial freezing for more than 30 days resulted in more tender meats.

The diet of cattle affects the composition and quality of beef, including its fat composition, flavour and colour. The study showed that partial replacement of barley with either of two forms of maize in cattle diets influenced the fat composition of beef but had minimal effects on its colour or off-flavour development during storage. The implication is that while partial inclusion of maize in beef cattle diets alters beef composition, it is unlikely to adversely affect quality perceptibly.

Urea is used at a large scale in diets for animals such as cows, goats and sheep, mainly to reduce production costs related to feeding. However, there is a concern about the risk of intoxication on livestock because of the fast release. We confirmed that carnauba wax is an efficient material for the slow release of urea in sheep diets because it provides better and safer nitrogen utilisation, helping ranchers to manage their animals.