In vitro development of Holstein and Japanese Black breeds embryo

Abstract: Two experiments were conducted with 3,457 oocytes, aspirated from the ovaries of slaugtered Holstein and Japanese Black breeds cows to compare the use of superovulated cow serum (SCS) and fetal calf serum (FCS) supplementation into medium for in vitro development (experiment I) and the effect of different sources of oocyte (experiment II). The endpoint was development to cleavage on day 2 and to blastocyt up to day 9 after insemination. In experiment I, oocyte were matured and cultured in vitro (after fertilization)in TCM-199 sipplemented with 5 % SCS or 5 % FCS. The cleavage rate of zygotes cultured in medium supplemented with 5 % SCS was higher (P<0,05) than 5 % FCS (562/860, 65,3 % vs 445.742, 60,0 %). The blastocyt production rate was significantly highe (P<0,01) in SCS treatment than FCS (232/860, 27,0 % vs 124/742, 16,7 %). In experiment II, 956 oocyte collected from Holstein breed and 899 oocyte from Japanese Black breed were matured in fertilized and cultured in vitro in medium supplemented with 5 % SCS. The mean oocyte number and blastocyt production per ovary were 12,0 (956/80) and 3,2 (252/80) for Holstein breed, 15,0 (899/60) and 3,1 (184/60) for Japanese Black breed. The cleavage rate of zygotes derived from Holstein and Japanese Black breeds ovaries was not significantly different . However, the blastocyst production rate was significantly higher in Holstein than Japanese Black breeds.