ASSOCIATION OF THE MOET AND OPU-PIV IN THE PRODUCTION OF BOVINE EMBRYOS

Abstract

It has been the aim to value, in Nelore cows, the association of the assisted reproduction MOET e OPU-PIV. For this, it has tested the ovarian superovulation (SOV) 48 to 60 h after the OPU (ovum pick-up) at a random phase of the estral cycle (OPU1) and the in vitro production (PIV) of recovered oocytes embryos (OPU2) in different moments after the prostaglandin F2? (PGF2?) application. The females (n=23) after the OPU1 received progestogen implant and 48 to 60 h after the OPU, then it has began the SOV, with FSH 180 mg / cows in 8 doses, for 4 days. In 6th and 7th applications of FSH, there were administered 500 µg of PGF2?  being the implants withdrawn in the 7th dose. After 12 h of the SOV, it was applied 25mg of LH to realize AI (artificial insemination) with fixed time. In the day of the embryos recovery 6 treatments were tested: T (0-144) (n=4), T (48-120) (n=5), T (48-96) (n=4), T (72-96) (n=3), T (96-72) (n=4), T (96-48) (n=3) which varied in accordance with moments of the PGF2?  administration and of OPU2 after the SOV. The PGF2?  administration in the embryo recovery (day 0) 0, 48, 72 and 96 h after the harvest and the OPU2 was 144, 96, 72 or 48 hours after the PGF2?. There was significant difference (p> 0,05) in the oocyte number when the near OPU of the PGF2?  was recovered, so that the recuperation in T (96-48) was significantly less when (48-96) was compared to T and T (72-96), (48 h after) damaged the oocyte recovery. We can conclude that is possible to carry out the association of the assisted reproduction without damaging the rates of production. Since the OPU takes place after lise of the present CLs in the ovaries after the superstimulation, in other words from 96 hours after the application of prostaglandin, after harvest of embryos in vivo.

KEY WORDS: Embryo, MOET, Nelore, oocyte, ovum pick-up.