DIÂMETRO FOLICULAR E FERTILIDADE DE VACAS MESTIÇAS LEITEIRAS SUBMETIDAS A PROTOCOLO DE IATF COM AJUSTES NO PROESTRO

Objetivou-se comparar protocolos de sincronizacao com uma e duas aplicacoes de um luteolitico simultâneas ou nao a gonadotrofina corionica equina (eCG) sobre o diâmetro do foliculo ovulatorio (DFOL) e a taxa de concepcao de femeas mesticas leiteiras ciclicas. Para tanto, no D0 foi iniciado o protocolo por meio da insercao de dispositivo de progesterona (P4) e aplicacao de 2,0mg de benzoato de estradiol. No D7 receberam 12,5mg de dinoprost trometamina. No D9 executou-se remocao dos P4 e aplicou-se 0,6mg de cipionato de estradiol. Nesse momento, as femeas foram subdivididas nos seguintes tratamentos: Grupo Controle - 2,5mL de solucao fisiologica, Grupo 2PGF - 12,5mg de dinoprost trometamina, Grupo eCG - 300UI de eCG, Grupo 2PGF+eCG - 300UI de eCG e 12,5mg de dinoprost trometamina. No D11 foi realizada ultrassonografia transretal (US) para determinar o DFOL e os animais foram inseminados. O diagnostico de gestacao foi realizado por US 55 dias apos. Os dados obtidos foram avaliados pelo SPSS considerando P≤0,05. O DFOL e as taxas de concepcao foram semelhantes entre os protocolos de sincronizacao. Conclui-se que em animais ciclicos a utilizacao de protocolos com uma unica dose PGF2α e sem suporte gonadotrofico do eCG parece proporcionar adequada resposta folicular e indices de fertilidade satisfatorios.

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