Vol. 11, Special Issue 11 (2022)

The aim of the study was to evaluate the effect of FSH stimulation on in vitro maturation, in vitro fertilization and blastocyst development rates of oocytes collected by ovum pick-up in Sahiwal cows. Sixty four Sahiwal cows aged 3-6 years randomly divided into two groups. Animals in group 1 (FSH stimulated, n=32) were subjected to FSH prestimulation with CIDR before OPU and Animals in group 2 were non stimulated (n=32). A total of 64 OPU sessions were performed in 64 animals with and without FSH prestimulation at random stage of estrous cycle. Performance was evaluated on per OPU session and per cow. The mean number of follicles available for aspiration (FSH stimulated;18.59± 1.04 and non-stimulated;6.5±0.25) and the mean number of oocytes recovered per session per animal (FSH stimulated; 9.87±0.39 and non-stimulated; 2.56±0.23) was found to be significantly (P< 0.05) higher in FSH stimulated group than the non stimulated group. The mean number of Grade A, Grade B, Grade C and Grade D oocytes recovered in non-stimulated group were 0.53±0.13, 0.71±0.11, 0.90±0.10, 0.40±0.10 and in FSH stimulated group were 2.37±0.47, 2.59±0.28, 3.03±0.33, 1.87±0.25, respectively. The mean number of oocytes recovered per session per animal was significantly (P< 0.05) higher in FSH stimulated group compared to the non-stimulated group The significance (P< 0.05) difference was observed between the non-stimulated and FSH stimulated group in Cumulus cell expansion rate (57.31% and 68.03%) and First polar body extrusion rate (46.34% and 56.32%).In FSH stimulated group 178 oocytes and in non-stimulated group 82 oocytes were kept for in vitro fertilization for 16-18 hrs and further in vitro culture for 7 days. The blastocysts development rate was observed on 6^th and 7^th day of culture. On 6^th and 7^th day the blastocyst development rate in FSH stimulated and non-stimulated group was 37.64% and 25.60% respectively, the blastocyst development rate was significant (P< 0.05) between non-stimulated and FSH stimulated group.