Efeito do mineral injetável na performance reprodutiva de Bovinos de Corte

Abstract

We evaluated the effect of injectable mineral supplementation in Nellore beef cows on reproductive performance, through estrus expression, pregnancy rate after 30 days of insemination and during final pregnancy. Nellore cows (n=433, multiparous) were placed to start the breeding season, using a hormonal protocol for estrous synchronization of the animals. The injection of the mineral was performed on the management called D0, which represents the first day of the protocol, using a completely randomized design. Cows that received the treatment were classified as TRAT and cows that did not receive were classified as CON. On the day of artificial insemination (AI), we collected information on the estrus rate, using a marker stick. The first gestational diagnosis was performed 30 days after AI and the second at 180 days. The results showed a trend (P = 0.07) in the expression of estrus for TRAT animals (46%) compared to CON animals (30%). In contrast, no difference was observed between pregnancy rates (P > 0.1). Consequently, we conclude that injectable mineral supplementation can contribute to improving the estrous expression response.