Desempenho de doadoras leiteiras mestiças F1 (Gir x Holandês) no sistema de produção in vitro de embriões

Abstract

Brazil currently has the third largest herd of dairy cattle in the world, composed mainly by F1 crossbreed animals (Gyr x Holstein), which are well adapted to tropical areas. The aim of this study was to evaluate the efficiency of Girolando donors in OPU and in vitro production of embryos (IVEP) using sexed semen of bulls from two breeds, Gyr and Holstein. We used data from 232 animals coming from different herds and the total of recovered oocytes was 4334. The oocytes were classified according to their viability and the viable ones (GI, GII and GIII) were used for IVP. The average of oocyte recovery from F1 donors was 18.14±1.33. There was no difference on the average of embryos considering the crossing F1 X Holstein (4.96±0.40) and F1 X Gyr (6.56±0.76). In conclusion, F1 donors showed a potential for being oocyte donors in the system of in vitro production of embryos, regardless the breed of the bull.