Superovulation of Nelore heifers with different FSH/LH doses and embryo freezing by one-step method with ethylene-glycol

• Autor(a) principal: Visintin, José Antonio
• Data de Publicação: 1999
• Outros Autores: Arruda, Rubens Paes de, Madureira, Ed Hoffman, Mizuta, Katia, Celeghini, Eneiva Carla Carvalho, Assumpção, Mayra Elena Ortiz D’Avila, Gusmões, Pedro Paulo Gimenes, Candini, Pedro Henrique
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Brazilian Journal of Veterinary Research and Animal Science
• Texto Completo: https://www.revistas.usp.br/bjvras/article/view/5740
• topic: Superovulacao; EmbriOes; Etilenoglicol; Bovinos.; Superovulation; Embryos; Ethylene-glycol; Cattle

The objetive of this study was to identify the better dose between 300 (n = 20), 400 (n = 21) and 500 IU (n = 21) of FSH/LH to stimulate Nelore heifers. The superovulation treatment started on day 10 (D0 = estrous) of the estrous cycle in 8 decreasing aplications for 4 days. The embryo recovery was achieved on day 6.5 after the first artificial insemination. The superovulatory response for 300, 400 and 500 IU FSH/LH was follicles (15.12, 15.76 and 14.94); corpus luteum (10.68, 11.55 and 10.81) and transferable embryos (5.20, 1.81 and 2.76). The 300 IU of FSH/LH group presented the best results in regard to transferable embryos. The transferable embryos were cryopreserved by one-step method with 1.5 M of ethylene-glycol, resulting in 8 pregnancies (7.5%) of 106 embryos transferred by non-curgical method. The 300 IU of FSH/LH presented better superovulatory response in comparison with 400 and 500 IU in Nelore heifers. The transfer of Bos taurus indicus embryos cryopreserved by one-step method in 1.5 M of ethilene glycol was not efficient.