Follicular Wave Synchronization Using GnRH Agonist in Jersey Crossbred Cows

Abstract

The study was aimed at recording the synchronization of follicular wave emergence in Jersey
crossbred cows when administered with GnRH on Day 5 of the cycle. initially, as a control study, the
normal follicular wave pattern were studied in Jersey crossbred cows (n=6) using ultrasound scanner.
During the subsequent cycle, all the animals were injected with GnRH agonist - Buserelin acetate (Inj.
Receptal; 10 μg i.m.) on Day 5 of the cycle and follicular wave pattern was studied: Monitoring the
normal follicular wa've pattern revealed that, out of six cows, three cows (50%) exhibited two waves and
three (50%) exhibited three waves per cycle with the mean days of emergence on 1.33 ± 0.90 and I 0.0 ±
0.34 and 1.67 ± 0.34, 9.67 ± 0.67 and 15.33 ± 0.88 respectively. Administration ofGnRH on day 5 of
the cycle caused ovulation of dominant follicle (8.92 ± 0.60 mm) a new follicular wave emerged by two
days of GnRH administration (Day7) in all the animals. In response to the GnRH administration normal
two wave cycles were altered to three wave cycles with the third wave emerging on the mean day of
14.6± 1.20 and there was no significant change among the three wave cycles. There was no significant
difference in the cycle length among the normal and GnRH treated cows (22.50 ± 0.83 vs 21.33 ± 1.49
days).