Key Laboratory for Animal Genetics and Molecular Breeding of Jiangsu Province, Department of Animal Science and Technology, Yangzhou University, Yangzhou-25009, China
*Corresponding Author: Yongjun Li, Key Laboratory for Animal Genetics and Molecular Breeding of Jiangsu Province, Department of Animal Science and Technology, Yangzhou University, Yangzhou-25009, China, Email: yzliyongjun@163.com
Online Published on 09 May, 2022.
The estrous synchronization has become a worldwide available solution for modern management and large-scale cultivation of sheep. The objective of the present study was to compare the efficacy of three estrus synchronization protocols, CIDR9+PGF2a+eCG; CIDR14+eCG and GnRH+PGF2a, in Hu sheep.
This study was conducted on 80 multiparous ewes, which were assigned into four groups: CIDR9+PGF2a+eCG; CIDR14+eCG; GnRH+PGF2a and control. Behavioral estrus was checked with teaser rams. Percentage of ewes behaving estrus at different time (0–24 h, 24–48 h, 48–72 h, respectively) was recorded. Pregnancy diagnosis was implemented on day 28 and confirmed on day 60 after insemination.
The results suggested that the estrus rate, pregnancy rate, conception rate, lambing rate and prolificacy in three treatment groups have no significant difference compared with control group. Most notably, CIDR9+PGF2a+eCG and CIDR14+eCG have significantly shorter duration of pregnancy than control. While CIDR14+eCG and GnRH+PGF2a did not dramatically change the fecundity of ewes, still CIDR9+PGF2a+eCG significantly decreased the fecundity of that compared with the control. Estrus responses in CIDR9+PGF2a+eCG, CIDR14+eCG and GnRH+PGF2a groups rose gradually to attain their significantly higher percentages (56.3%, 52.9% and 66.7%, respectively) during 24–48 h post-estrous detection, afterwards, they fell down.
CIDR, GnRH, Reproductive performance, Synchronous estrus
