Proteomic profile of seminal plasma from Pêga donkeys (Equus asinus) with high sperm motility and vigor: Implications for assisted reproduction.

Donkeys of the Pêga breed (Equus asinus) have been used for two centuries to produce breeding stock and create hybrids for labor and transport in southeast Brazil, and for exporting meat and milk to other countries. Furthermore, they are used in competitions, as they are docile and easy to handle. However, assisted reproduction success rates for frozen donkey semen are remarkably low, with no standardized method for cryopreserving sperm after removal of seminal plasma.

Calving date as a potential predictor for the probability of approval in the first breeding soundness evaluation of Nellore bulls.

Beef production systems primarily use natural service (NS) for breeding. However, a significant number of bulls used for NS are subfertile, limiting the profitability of the cow-calf operations. Therefore, producers should select bulls based on breeding soundness evolutions (BSE) to ensure higher pregnancy rates.

Dietary L-arginine supplementation during early gestation of gilts affects conceptuses development.

l-arginine supplementation of sows has led to improvement of reproductive performance, but the mechanisms responsible for the positive effects of arginine during gestation on conceptuses survival and development are still poorly understood. Thus, we aimed to evaluate effects of 1.0% l-arginine supplementation (ARG) on phenotypic traits of commercial gilts, embryos and fetuses, concentration of gilts' blood metabolites, expression of developmental and cellular apoptosis genes in conceptuses of 25 and 35 days.

Soybean grain is a suitable replacement with soybean meal in multiple supplements for Nellore heifers grazing tropical pastures.

The research aimed to evaluate the effect of replacing soybean meal with soybean grain on the nutritional parameters and productivity of heifers grazing on Urochloa decumbens in the rainy-dry transition period. Forty crossbred heifers with the initial age and weight of 18 months and 292 ± 6.1 kg, respectively, were used.

Estimation of daily milk yield of Nellore cows grazing tropical pastures.

Beef cows' milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows.