Setting up Cows for First Postpartum Artificial Insemination

A long standing goal of reproductive physiologists was to develop a hormonal synchronization program that could overcome the problems and limitations associated with visual detection of estrus in dairy cattle. This goal was realized in 1995 with the publication of a hormonal synchronization protocol that combined GnRH and PGF2α to control ovarian physiology and is now commonly referred to as the Ovsynch protocol (Pursley et al., 1995). The Ovsynch protocol synchronizes follicular development, luteal regression and ovulation such that artificial insemination can be conducted at a fixed-time without the need for estrus detection, commonly referred to as timed artificial insemination (TAI). Subsequent studies that repeated this work soon verified the results of the original publication (Burke et al., 1996; Pursley et al., 1997a,b), and dairy producers and veterinarians began to implement the Ovsynch protocol as a tool for reproductive management on commercial dairies. In the nearly 15 years since this first publication, today many dairy farms in the U.S. and around the world have adopted systematic synchronization protocols as a routine strategy for submitting cows for first and greater postpartum AI service (Caraviello et al., 2006).