Improvement of bovine in vitro embryo production by fetal calf serum and cysteamine supplementation and investigation of freezability

The aim of this study was to investigate the effects of cysteamine (Cys) and fetal calf serum (FCS) in synthetic oviduct fluid (SOF) and charles and rosenkrans (CR1aa) on the bovine in vitro embryo production and its ability of freeze. The oocytes were divided into two groups and allowed to mature in TCM-199, with and without cysteamine. They were divided into 4 subgroups according to whether they contain Cys and FCS in 2 different culture media (SOF and CR1aa). Accordingly, 8 groups were formed as SOF+FCS+Cys, SOF+Cys, SOF+FCS, SOF, CR1aa+FCS+Cys, CR1aa+Cys, CR1aa+FCS and CR1aa. Embryos were cultured for 7-9 days and were frozen using vitrification method. Development of embryos was observed during the first 24 hr post-thaw period. The highest rate of compact morula was 20% in SOF+FCS+Cys and 19.4% in CR1aa+FCS+Cys. The rate of blastocyst in SOF+FCS and CR1aa+FCS were found 17.9% and 15.4% respectively and the difference between groups was statistically significant (P<0.05). During the 12 hr vitality assessment, the highest rate was determined in SOF+FCS (47%). The results indicate that FCS has a positive effect in reaching compact morula and blastocyst regardless of the presence of the culture medium or antioxidant used. There was no statistically difference between the values of post-thaw embryos.