INFLUENCE OF DOMINANT FOLLICLE DIAMETER AT THE TIME OF FTAI ON PREGNANCY RATE IN NELORE COWS - DATA SURVEY

Abstract

This study aims to evaluate the influence of the dominant follicle diameter in the moment of the artificial insemination in the pregnancy score in Nelore cows, submitted to the same FTAI protocol. To accomplish this study, a load of 95 multiparous cows were used. The FTAI protocol used to synchronize these was: on day 0 (D0) an intravaginal progesterone device (P4) was introduced together with the application of 2mg of estradiol benzoate intramuscularly. (IM). Then, eight days later (D8) the P4 device was removed and 1mg of Estradiol Cypionate (EC), 526 mcg of Sodium Cloprostenol and 300UI of Equine Chorionic Gonadotropin (eCG) was applied IM. 48 hours after the device was removed (D10) transrectal ultrasound was performed in each of these animals to evaluate the ovaries and measure the diameter of the dominant follicle, after which they were inseminated. At 30 days, transrectal ultrasound was performed again, but for pregnancy diagnosis. The data obtained were compared and calculated with the diameter of the dominant follicle on the day of AI. The results were considerable on the pregnancy rate.