ESTRADIOL E GNRH NA SINCRONIZAÇÃO DO ESTRO E INDUÇÃO DA OVULAÇÃO DE VACAS MESTIÇAS

Autores

DOI:

https://doi.org/10.1590/1983-21252020v33n325rc

Palavras-chave:

Benzoato de estradiol (EB). Biotecnologia. Cipionato de estradiol (EC). Reprodução.

Resumo

Benzoato de estradiol (EB), cipionato de estradiol (EC) e hormônio liberador de gonadotrofinas (GnRH) foram avaliados como indutores da ovulação na IATF em vacas mestiças em lactação. No experimento I (n=45) a dinâmica folicular foi avaliada, enquanto no experimento II (n=171) a eficiência reprodutiva foi avaliada. Todas as fêmeas foram submetidas a um protocolo de sincronização: inserção no dia 0 (D0) de dispositivo intravaginal de liberação de progesterona (PRID; 1g) mais administração de EB 2mg; D8, remoção de PRID, administração de 0,150mg de PGF2α e 400 UI de eCG, e as vacas foram alocadas em três tratamentos: 1) TEB9 - administração IM de 1mg EB em D9 e AI realizada 52 horas após a remoção PRID; 2) TEC - administração IM de 1mg EC em D8 e AI realizada 48 horas após a remoção de PRID; e 3) TGnRH - administração de 100µg GnRH em D10 e AI realizada 52 horas após a remoção de PRID. A taxa de crescimento folicular foi menor no grupo EC (p <0,05). Não houve efeito dos tratamentos nas taxas de ovulação e prenhez (p >0,05). O uso de EB, EC e GnRH como indutores de ovulação em protocolos de IATF não mostrou diferenças marcantes nos padrões avaliados de dinâmica folicular e prenhez.

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Publicado

31-07-2020

Edição

Seção

Medicina Veterinária