Select Sires

Maximizing the Success of Ovsynch
Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired May 9, 2002

Many producers have adopted the Ovsynch fixed time A.I. protocol with tremendous success. This protocol uses an injection of GnRH followed seven days later with an injection of prostaglandin. At 48 hours after the prostaglandin cows are given a second injection of GnRH and are inseminated without estrous detection eight to 18 hours later. Most herds can expect 30 to 35 percent of treated cows to conceive to this fixed time A.I. This is extremely efficient reproductive management when we consider that conventional reproductive management programs seldom achieve greater 20 to 25 percent pregnancy rates after 21 days of heat detection. However, the following are a few tips to help maximize success to the Ovsynch program and hopefully generate a few extra pregnancies. First, it’s important to remember that cows don’t read the book. I’ve tried to teach them but it just seems to waste my time and annoys the cow. Eight to 10 percent of Ovsynch treated cows do not respond to the first GnRH and will show heat around the time of the prostaglandin injection. An additional 10 percent may show heat between the prostaglandin and GnRH injections. These are normal heats that should be bred when detected and subsequent hormone injections are not administered. If not detected, few of these cows are likely to conceive to fixed time A.I. resulting in wasted hormones, semen, and labor. The percentage of cows displaying these "early heats" can be reduced and pregnancy rates improved by pre-synchronizing cows to a stage of the estrous cycle that is conducive to optimum response to the Ovsynch protocol. Presynch is accomplished by giving two prostaglandin injections at 14-day intervals, with the last injection being 12 to 14 days prior to the initiation of Ovsynch. Presynch works well in herds that currently use prostaglandins as postpartum therapeutic treatment. Research has shown Presynch can improve conception rates to Ovsynch by as much as five to 15 percent. For more information on Ovsynch or Presynch contact your veterinarian or your local Select Sires Reproductive Solutions™ specialist.

™Reproductive Solutions is a trademark of Select Sires Inc.

Copyright 1996-2002 Select Sires Inc. Last updated 15-Jul-2002.

Select Sires Inc., 11740 U.S. 42 North, Plain City, Ohio 43064 / Phone: (614) 873-4683 Fax: (614) 873-5751