ABSTRACT
A study was conducted on 851 cows (Gir cows and their crossbreeds) between 1971 and 1984 at the Livestock Farm of the All India Coordinated Research Project on Cattle in Jabalpur, India. The cows were impregnated with frozen or fresh semen from 90 bulls and a total of 2699 pregnancies resulted. An overall incidence of prenatal mortality was recorded at 4.89%. A significantly higher (P / 0.01) incidence of prenatal mortality was encountered in three breed crosses in comparison with Gir cows and their first generation crossbreeds. Parity of dam had no effect on prenatal mortality. However, effects of season and individual sires on prenatal mortality were documented. It was observed that reproductive performance was improved significantly after prenatal mortality.