Delayed ovulation is a condition where ovulation is delayed. the cause of delayed ovulation in cattle is due to the lack of LH and FSH hormones in the blood. The study was conducted to determine the size and development of follicles in Belgian Blue and PO cattle diagnosed with Delay Ovulation. The research was conducted from October 2022 to December 2022 at BPTU HPT Sembawa, Banyuasin Regency, …