A preliminary study to evaluate the effect of metformin on folliculogenesis and ovulation rate in sheep

A preliminary investigation was conducted to assess the effect of metformin on folliculogenesis, ovulation rate and blood metabolites in Malpura sheep inserted with intravaginal progesterone sponge. The study was conducted during August, 2022. Ewes in treatment group (n=20) were orally administered with metformin @ 500 mg once daily for two weeks as against untreated controls (n=20). Preovulatory follicle number (1.60±0.13) and corpus luteum number (1.53±0.14) were non-significantly higher in treated group than control (1.30±0.10 and 1.25±0.10). Relatively, a higher proportion of multiple ovulations were recorded in treatment group than control (55 vs. 25%). Besides, blood levels of total cholesterol (P<0.01) and LDL-cholesterol (P<0.05) were reduced significantly after treatment, while plasma-glucose, HDL-cholesterol and triglyceride remained comparable between the groups. The findings suggest that metformin has a folliculogenic and ovulation promoting effect in sheep. However, detailed studies are warranted to investigate its effect and underlying mechanism.