Utilization of a 5- or 14-day progestin-based estrous synchronization protocol with sorted semen in beef heifers
DOI:
https://doi.org/10.21423/aabppro20123954Keywords:
estrous synchronization, controlled internal drug-release insert, gonadotropin releasing hormone, prostaglandin, sorted semenAbstract
Estrous synchronization protocols that utilize progestin via a controlled internal drug-release insert (CIDR) in conjunction with gonadotropin releasing hormone (GnRH) and prostaglandin (PG) treatments have been shown to be effective in beef heifers. Sorted semen is more costly than unsorted semen; thus, AI pregnancy rates need to be maximized when sorted semen is used. The objective of this study was to compare the effectiveness of a 5-day versus a 14-day CIDR protocol when sorted semen is utilized for AI in beef heifers. A secondary objective was to determine the effect of timing of insemination on pregnancy rates when using sorted semen.