The Effect of Artificial Insemination Timing on the Sex Ratio of Offspring and Fertility in Dairy Cows

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

Pages : 21-24

View : 17 | Download : 3

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The aim of this study was to investigate the effect of the interval between artificial insemination and the onset of estrus on the sex ratio of offspring and fertility in Holstein cows. Standing to be mounted behavior was considered the beginning of estrus, and artificial inseminations were performed 6 h insert ignore into journalissuearticles values(Group 1);, 9 h insert ignore into journalissuearticles values(Group 2);, 12 h insert ignore into journalissuearticles values(Group 3);, and 15 h insert ignore into journalissuearticles values(Group 4); after the onset of estrus in cows. Overall 119 insert ignore into journalissuearticles values(n: 85);, 107 insert ignore into journalissuearticles values(n: 72);, 120 insert ignore into journalissuearticles values(n: 80); and 119 insert ignore into journalissuearticles values(n: 83); artificial inseminations were performed in Groups 1, 2, 3 and 4, respectively. Pregnancy rates were 67.1%, 70.8%, 72.5% and 79.5% in Groups 1, 2, 3 and 4, respectively insert ignore into journalissuearticles values(P = 0.33);. The highest female ratio of offspring and the pregnancy loss ratios were obtained in Group 2 but this difference was not significant insert ignore into journalissuearticles values(P = 0.54, P = 0.64);. The highest twinning ratio was obtained in Group 4. The number of artificial inseminations per pregnancy was within the economical limits in all groups. In conclusion, the results of this study indicate that the interval between the onset of estrus and artificial insemination time does not alter the sex ratio of offspring in dairy cows with normal fertility parameters.
Keywords : Cow, artificial insemination time, sex ratio, fertility parameters