Use of melengestrolacetate after use protocol to artificial insemination at fixed-time in Nellore cows pluriparous

Objective was to evaluate the effects of supply 2.28 g MGA® Premix between the 13th and 17th day after fixed-time artificial insemination (TFAI), on pregnancy rate of multiparous Nellore cows. It used 154 cows, divided randomly into two lots, Treatments 1, n = 55 and Treatments 2, n = 99. The treatments 1 received only one mineral supplement and treatments 2 received the same batch mineral supplement added 2.28g MGA® Premix/animal/day. We used descriptive statistics for frequency table, on program SAS, by the interaction of supply MGA® Premix with the rate of pregnancy. The pregnancy rate was higher for cows supplemented MGA® Premix evaluated at 43 days of pregnancy. Using TFAI after MGA® Premix increases the rate of embryo survival and rate of pregnancy.

body condition score; progestin; order of birth; synchronization of estrus; zebu

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