Follicular dynamics of induced estrus of females from the Pantaneira breed

Ferreira, Mariane Gabriela Cesar RibeiroSouza-Cáceres, Mirela BrochadoOliveira-Brochado, Níkolas Cáceres deOliveira Júnior, Jair SábioOliveira, Marcus Vinicius Moraes deMelo-Sterza, Fabiana de Andrade

The aim of this study was to evaluate the performance of heifers from the Pantaneira breed in FTAI programs and characterize follicular dynamics after induced estrus synchronization programs. The pregnancy rate observed in an FTAI program (36,4%) followed by the AI of estrus return was 45.5%. The study of follicular dynamics revealed that females from this breed, on average, show ovulation 77 hours after the withdrawal of the progesterone device, being therefore later than in other bovine breeds. The results suggest that the late ovulation of the females submitted to estrus synchronization programs may negatively influence their pregnancy rates.(AU)

1. Estrous cycle
2. Adapted breed
3. Conservation
4. Reproduction