University researchers, along with support from industry partners like Pfizer Animal Health, are looking into ways to improve dairy cattle fertility. One result of this effort has been the use of the 5-Day CO-Synch + EAZI-Breed™ CIDR® estrus synchronization protocol, a standard protocol in the beef industry.
Today, researchers are looking into how the beef timed-A.I. program can benefit dairy cows as well. The theory is that the protocol better synchronizes a cow’s estrous cycle so that A.I. can be administered when cows are more fertile.
The 5 day CO-Synch + CIDR involves administering GnRH and a CIDR on day -5, removing the CIDR and giving a dose of prostaglandin on day 0, administering a second injection of PGF approximately eight to 12 hours after CIDR removal to ensure corpus luteum regression, and A.I. concurrent with GnRH-2 administration on day three (72 hours following the initial dose of prostaglandin).
Results from beef cattle experiments show the protocol offers a 17.5% increase in pregnancies. Trials with dairy heifers and cows are underway at the University of Florida and other locations across the country to determine the potential to increase fertility with a five-day interval between GnRH and prostaglandin and the appropriate prostaglandin treatment to use.
Source: Dairy Cattle Reproduction Council (Research sponsored by Pfizer Animal Health)