Effect of different doses of FSH on superovulation, production and quality of embryo in North Omani Cattle breed

The experiment was conducted to investigate the Ovarian response and embryo quality using different doses of follicle stimulating hormone (FSH-P) in North Omani Cattle breed (NOC) in order to determine the suitable dose. Eighteen donor NOC were divided into three groups (G1, G2, and G3) comprising of six cows in each group and treated with 20 (G1), 25 (G2) and 30 mg FSH (G3). Ovarian response was recorded as development of corpus luteum (CL), unovulated follicles (UOF), unfertilized ova (UFO), recovered embryo (RE) and transferable embryos (TE). Embryos were flushed seven days after the first AI and classified according to the developmental stage and quality. Results showed that, cows superovulated with FSH (G3) increased significantly (P<0.05) number of CLs and number of RE (6.83 and 5.33 /flushed cow) compared with the G1 of FSH (3.17 and 2.00/flushed cow) and G2 (4.67 and 3.00/flushed cow). While using FSH in (G2) increased significantly (P<0.05) the number of TE (excellent and good) quality, decreased average number of UOF and UFO (2.84, 3.33 and 0.67/flush) compared with FSH G3 (1.83, 5.67 and 1.50/flush). While no significant difference was observed in TE number between G1 and G2. G3 groups producing embryos at early stages of development (4 and 8 cells) and this was undesirable for embryo transfer program as this treatment (30 mg) produced more number of fair, poor and degenerated embryos compared with 20 and 25 mg FSH. Consequently, 25 mg FSH dose increased number of TE, decreased number of UOF and UFO, and that was the suitable dose for superovulation of NOC.