Characterization of Postpartum Ovarian Follicular Development Pattern in Crossbred Cows

Abstract

Background: The postpartum period is crucial for cattle reproduction. The length of postpartum anestrus significantly impacts reproductive efficiency. Apparently enhanced energy attribution to milk production may lead to anestrus by delaying the onset of follicular activity. The absence of an ovulation stimulus, rather than insufficient follicle growth, determines the limited duration until ovulation. The current study was aimed to document the postpartum ovarian dynamics in crossbred Jersey cows. Methods: The study was conducted in ten postpartum crossbred Jersey cows. Transrectal ultrasonography was performed to record the follicular development pattern from parturition till two ovulation or 90 days postpartum on alternate days. The data was analyzed for follicular wave emergence, no of follicular waves, size of the dominant follicle and ovulatory status. Result: Fourty per cent of crossbred Jersey cows showed cyclicity and rest 60 per cent of cows are in anestrum. The mean diameter size of the dominant follicle in ovulated cows is 12.2±1.2 mm and in anestrum cows is 10.6±0.4 mm. The first wave emergence is 5.7±0.3 and 10.8±5.9 day in OV and NOV group respectively. In conclusion significant difference could be observed in emergence of first, second, third, fourth and fifth follicular wave emergence, growth phase duration, rate, size of the dominant follicle and duration of wave between postpartum ovulated and anestrum cows.