Reproductive performance in beef heifer submitted to FTAI with protocol BE-base or Ovsynch modified

Abstract

The reproductive performance of 217 beef heifers submitted to different FTAI protocols and clean up bulls was evaluated. The animals were randomly divided in three groups. The group 1 (G1; 118 heifers) was exposed to a protocol modified of Ovsynch, with inclusion of a progesterone device (P4). The group 2 (G2; 50 heifers) was differed the G1 to application of estradiol benzoate (EB) as ovulation inducer. The group 3 (G3; 49 heifers) was submitted to a protocol with EB, P4 and PGF2α. Seven days after FTAI, all heifers were exposed to bulls. The statistical analyzes were performed using Chi-square and variance methods (P = 0.05). The pregnancy rate to FTAI was higher by G1 (57,6%; P < 0.05) than G2 (34.0%) and G3 (34.7%), which did not differ. The final pregnancy rate did not differ among groups. The G1 group protocol was superior than G2 and G3 when evaluating the pregnancy rate. The final pregnancy rate did not differ among groups, regardless of the protocol used.