Parâmetros reprodutivos de cabras Toggenburg inseminadas com sêmen resfriado, após diluição em meio à base de gema de ovo

Abstract

The conception rate, the prostaglandin response, the estrus duration, the reproductive class, and the mucous of goats inseminated with semen diluted in egg yolk extender and cooled at 5°C, for 12 or 24 hours were evaluated. Sixty-two female goats and two sexually mature Toggenburg bucks were used. The females received two doses of 22.5μg of prostaglandine F2α, at 10-day intervals. After the first injection, the estrus was monitored three times a day (6:00, 12:00, and 18:00h), with a buck teaser. Only one insemination was used. The percentages of animals that showed estrus after the first and the second injection of PGF2α were 85.5% and 88.7%, respectively. The average intervals from first and second PGF2α injection to estrus were 41.04±20.32 and 45.67±9.28h, and the estrus durations for both injections were 40.02±15.96 and 32.24±12.09h, in this order. The interval from the PGF2α injection to the beginning of the estrus was longer (P<0.05), whereas the estrus duration was shorter (P<0.05) in the estrus induced after the second PGF2α injection. The total conception rate was 49.1%. Neither the semen storage length (12 or 24 hours) nor the reproductive class did not affect (P>0.05) the conception rate. The mucous observed at the insemination time influenced (P<0.05) the fertility of inseminated goats, with the striated aspect associated to higher fertility.