Effect of Season on Ovulatory Response and Reproductive Performance in Noncyclic Lactating Dairy Cows Synchronized with Ovsynch

Authors : Barış GÜNER, Ebru KARAKAYA BİLEN

Pages : 98-105

Doi:10.53518/mjavl.1165972

View : 24 | Download : 12

Publication Date : 2022-12-26

Article Type : Research Paper

Abstract :The aim of this study was to compare the ovulatory response and reproductive performance after Ovsynch protocol in noncyclic dairy cows during the warm insert ignore into journalissuearticles values(n = 43); and cool seasons insert ignore into journalissuearticles values(n = 70);. Noncyclic cows insert ignore into journalissuearticles values(n=113); received Ovsynch protocol; GnRH1 insert ignore into journalissuearticles values(d 0);; PGF2α insert ignore into journalissuearticles values(d 7);; GnRH2 insert ignore into journalissuearticles values(d 9);; FTAI insert ignore into journalissuearticles values(d 10);. Ultrasonographic examinations were performed to determine the preovulatory follicle size insert ignore into journalissuearticles values(d 0, d 10); and ovulatory response to the GnRH1 insert ignore into journalissuearticles values(d 7); and GnRH2 insert ignore into journalissuearticles values(d 17);. Follicle size at the onset of Ovsynch was not different in cool season insert ignore into journalissuearticles values(20.8 ± 0.9 mm); compared to that in warm season insert ignore into journalissuearticles values(19.1 ± 1.1 mm, P > 0.05);. The percentage of small-sized follicles at the onset of Ovsynch was higher insert ignore into journalissuearticles values(P < 0.05); in warm season insert ignore into journalissuearticles values(37.2%); than cool season insert ignore into journalissuearticles values(18.6%);. However, follicle size at FTAI was similar insert ignore into journalissuearticles values(P > 0.05); between warm insert ignore into journalissuearticles values(15.3 ± 0.3 mm); and cool insert ignore into journalissuearticles values(15.8 ± 0.3); seasons. Ovulatory response to the GnRH1 and the GnRH2 of Ovsynch were not different during the warm insert ignore into journalissuearticles values(90.7%, 83.7%); and cool seasons insert ignore into journalissuearticles values(81.4%, 87.1%);, respectively insert ignore into journalissuearticles values(P > 0.05);. Pregnancy rate was also similar insert ignore into journalissuearticles values(P > 0.05); during the warm insert ignore into journalissuearticles values(34.9%); and cool seasons insert ignore into journalissuearticles values(35.7%);. Cows that had large-sized follicles at the onset of Ovsynch had a tendency insert ignore into journalissuearticles values(P = 0.08); for lower pregnancy rate in warm season insert ignore into journalissuearticles values(12.5%); compared to cool season insert ignore into journalissuearticles values(52.6%);. It was concluded that season did not affect the ovulatory response to the first GnRH and pregnancy rate in noncyclic dairy cows that were synchronized with Ovsynch.
Keywords : Cool, Noncyclic, Ovsynch, Warm, Season