Analysis of the influence of the birth period on the body weight of Nelore cattle

Abstract

This study aimed to present the relationship between the birth period of beef cattle and the weaning weight of Nelore calves. A total of 260,832 Nelore animals from the database of the National Association of Breeders and Researchers (ANCP) were used. Out of this total, 130,001 were males (49.84%) and 130,831 were females (50.16%) of the Nelore breed conceived via artificial insemination. The animals used were born between the years 2014 and 2017 in the Southeast and Midwest regions in different months of birth. The evaluated characteristic was the weaning weight, and the assessment of these weights was defined at 210 days (standard weaning age). It was observed that there were no significant differences (P>0.05) in weaning weight between the years of birth. However, among the birth months, significant differences (P<0.05) in weaning weight were observed, with animals born between July and October (dry season) showing higher average weights. Therefore, it was concluded that the month of birth of Nelore calves can influence the weaning weight at 210 days of age, emphasizing that the weaning month is directly related to the weight gain of the animals. Therefore, a well-defined breeding season is necessary to control the ideal months for weaning heavier animals.