Influência de fatores não genéticos nos parâmetros produtivos de vacas submetidas a inseminação artificial em tempo fixo (IATF)

Abstract

This study aimed to evaluate the influence of non-genetic factors on the productive and reproductive parameters of beef cows subjected to Fixed-Time Artificial Insemination (FTAI) on farms in the municipality of Corrente, Piauí. The study was conducted on 5 farms, involving 484 female cattle distributed in different categories, subjected to two hormonal protocols. Body condition score (BCS), weight, animal category (heifer, primiparous, multiparous), month of insemination, and type of hormonal protocol were evaluated using generalized linear mixed models (GLMM). Pregnancy rates varied from 23.5% to 62.5% among farms, with an overall average of 53.1%. BCS and body weight showed an effect (P < 0.05) on pregnancy rate, confirming the importance of nutritional status and positive energy balance in reproductive efficiency. In the IATF (Artificial Insemination at Fixed Time), the hormonal protocol and animal category showed no influence (P > 0.05), suggesting that environmental conditions and balanced management between groups minimized variations. Therefore, adequate nutrition, maintenance of ideal body condition score, and efficient reproductive management are determining factors for the success of IATF, reinforcing that reproductive performance depends more on environmental and management factors than on genetic differences between the cows evaluated.