Desempenho reprodutivo de novilhas primíparas e desempenho de bezerros desmamados precocemente

Abstract

The weaning process in beef cattle should primarily target cows to ensure that they enter the dry season with good body condition, free of nutrient demand for milk production, allowing them pass for the critical period without impair their reproductive function. Based on this information, aim of his work was to improve the reproductive performance of primiparous heifer, and evaluate the performance of calves weaned early at 60-90 days. The work was conducted in the period from December 2016 to May 2017, at Santa Cecília de Fernando de Paula Cardoso farm, located in Dom Pedrito-RS. Were used 58 calves, 29 females and 29 males, sons of primiparous heifers, with three years old, of the Red Brangus breed, born in the calvin period from August to Sepetember 2016, from artificial insemination (period of 45 days) and natural mount (period of 15 days). The calves were weaned early on December 9th, 2016, with average weight of 106 kg. For weighing, was used a conventional bovine balance, installed on the farm. The calves were supplemented in the corral for seven days, with a 17% protein ration, 1.5% of their live weight per day. After the conduction, was observed 84,48% of pregnant primiparous heifer. The weight gain, evaluated through the body condition score, after early weaning of heifers, was one of the main factors that influenced the high pregnancy rate. The 58 calves submitted to early weaning had an initial average weight of 106,27 kg, and final of 161,23 kg. The early weaning is a technique that aims to improve the female reproductive indices, without hampering the development of calves, therefore it’s of fundamental importance to offer adequate feeding conditions to not harm the future development of the calf.