The Effectiveness of Cosynch Protocol in Dairy Heifers and Multiparous Cows

Authors : Orkun DEMİRAL, Mustafa ÜN, Murat ABAY, Tayfur BEKYÜREK, Ahmet ÖZTÜRK

Pages : 213-217

View : 26 | Download : 8

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The aim of the present study was to evaluate the effects of Cosynch protocol on some reproductive parameters in Holstein multiparous cows insert ignore into journalissuearticles values(MC); insert ignore into journalissuearticles values(n = 54); and heifers insert ignore into journalissuearticles values(n = 53);. Follicular development, presence of corpus luteum insert ignore into journalissuearticles values(CL); at different stages of Cosynch protocol, ovulation time and pregnancy rates were evaluated by ultrasonography in MCs and heifers. Pregnancy rates insert ignore into journalissuearticles values(PR); in MCs and heifers were found as 41% and 51% insert ignore into journalissuearticles values(P: 0.29, Z: -1.06);. At the time of first Gonadotropinreleasing hormone insert ignore into journalissuearticles values(GnRH); insert ignore into journalissuearticles values(GnRH1);, Prostaglandin F2a insert ignore into journalissuearticles values(PGF2a); and final GnRH insert ignore into journalissuearticles values(GnRH2); injections, PRs in heifers and MCs which had CL on their ovaries were detected as 47.4%-48.7% insert ignore into journalissuearticles values(P: 0.91, Z: 0.12);, 60.5%-48.7% insert ignore into journalissuearticles values(P: 0. 30, Z: -1.4); and 62.1%-36.4% insert ignore into journalissuearticles values(P: 0.031, Z: -2.15); respectively. Ovulations occurred in 24-30 h interval after artificial insemination insert ignore into journalissuearticles values(AI); in MCs insert ignore into journalissuearticles values(50%); and heifers insert ignore into journalissuearticles values(35%); insert ignore into journalissuearticles values(P: 0.13, Z: 1.51);. In conclusion, Cosynch protocol was found more effective and practical in heifers than MCs. In addition, ovulations that occurred before AI could be the reason of low conception rate for Ovsynch procedure in heifers.
Keywords : Multiparous cows, heifer, pregnancy rates, corpus luteum, ovulation synchronization