Protocols with Different Time of Progesterone Exposure on Superestimulatory Response and Embryo Production of Locally Adapted Curraleiro Pé-Duro Cows

摘要

The purpose of this study was to evaluate embryo production and embryonic quality of locally adapted Curraleiro Pé-duro cows, using protocols with different progesterone exposure. Cows were divided in three groups: Control, P24 and P36. All cows had the estrus previously synchronized and in the fifth day of the estrus cycle, the cows of the groups P24 and P36 received an intravaginal progesterone device and estradiol benzoate. Starting from the ninth day of the cycle, all cows received eight decreasing doses of FSH and two doses of D-cloprostenol together with the two last doses of FSH. Treatments P24 and P36 had the progesterone device removed 24 and 36 hours after the first application of D-cloprostenol, respectively. All cows received lecireline in the thirteenth day, with the inseminations accomplished 12 and 24 hours later. There was no difference (P > 0.05) for superestimulatory response among treatments. The number of total structures was greater (P < 0.05) in P24 than in the Control and the number of viable structures was greater (P < 0.05) in both P24 and P36 than in the Control. The use of exogenous progesterone in superovulation protocols improved embryo production and quality of locally adapted Curraleiro Pé-duro cows.