Influência da estação de nascimento de bezerras girolando no desenvolvimento na fase de cria e desempenho reprodutivo e produtivo

Abstract

Raising calves is one of the most important activities within dairy cattle farming, as they will be the replacement animals for the herd. At this stage, management must be efficient so that the production results of the adult animal and the profitability of the property are achieved. With this, the objective was to evaluate the effect of the calf's birth season on development in the calf phase and reproductive and productive performance. The experiment was conducted at the Glória Experimental Farm, at the Federal University of Uberlândia. 74 calves born from January/2018 to March/2020 were evaluated, from the first day of life to the end of the first lactation. The animals were categorized according to the season of birth: spring/summer (October to March) and autumn/winter (April to September). During breastfeeding, the weight of the animals was evaluated on days: 0, 30, 60 after birth and at weaning. Rectal temperature, stool score, food intake and animal behavior were monitored daily. In adulthood, the first lactation date was collected and milk production was monitored during the first lactation. The variables analyzed were: weight gain during lactation, occurrence of diseases during the lactation phase, percentage of heifers that gave birth, age at first calving and average milk production in the first lactation according to the season of birth. Continuous variables were analyzed by analysis of variance and binomial variables by logistic regression in the MINITAB program. It is concluded that under the conditions of the current experiment, calves born in the autumn/winter season have greater weight at 30 days of age, however this difference was compensated during lactation, without interfering with reproductive and productive performance.