Sincronização do estro e da ovulação em gado de corte. Base endócrina e protocolos utilizados
Palavras-chave:
ciclo estral, surtos de crescimento folicular, sincronização do estro e da ovulação, vacas de corteResumo
No México, a eficiência reprodutiva das vacas em sistemas de produção de bezerros é baixa e o uso de esquemas de sincronização do estro e da ovulação pode contribuir para melhorá-la. O objetivo desta revisão foi descrever a regulação endócrina do ciclo estral e a dinâmica folicular em bovinos, destacando como, por meio do uso de hormônios exógenos, esses processos podem ser manipulados para implementar diferentes protocolos de sincronização do estro e da ovulação. Além disso, os resultados da taxa de prenhez no estro sincronizado (TPES) são apresentados com os diferentes protocolos de sincronização do estro e da ovulação relatados na literatura. Foram coletadas revisões e artigos originais sobre o ciclo estral e o desenvolvimento folicular em bovinos, e os dados da TPES foram obtidos de artigos científicos publicados entre 2000 e 2023. O TPES relatado varia de 23 a 76 %; no entanto, embora a faixa seja ampla, em protocolos baseados em estradiol e GnRH, cerca de 50 % dos dados de TPES coletados estão entre 45 e 55 %. Nos protocolos baseados em progesterona, 50 % dos dados relatam TPES entre 55 e 65 %. Atualmente, existem três protocolos principais de sincronização de estro e ovulação com os quais, de acordo com a literatura revisada, é possível obter TPES de 45 a 65 % na maioria dos casos.
http://dx.doi.org/10.21929/abavet2023.16
e2022-11
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