Synchronization Programs
Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired Nov. 23, 2006
With Ray Nebel,
Senior Reproduction and Herd Management Specialist, Select Sires Inc

Ray, this week we are talking about synchronization. You are fresh off a trip from Denver, where they came up with some new ideas. Tell us about them.

Yes, Bill, last week was a Dairy Cattle Reproductive Council meeting, which was the first of hopefully many to come. We had 330 individuals, dairy producers and industry people that got together on a day and a half session talking all about dairy cattle reproduction. During this conference, we came up with basically a new synchronization program for first service that really looks promising and a number of producers, primary in the upper Midwest, have tried and have had encouraging results. The beginning of the program is very similar to what we use now in a pre-synchronization, where we have two prostaglandin injections; the first two prostaglandin injections are 14 days a part, and then the second prostaglandin injection is 12 days prior to the start of the real synchronization part of Ovsynch, which is GnRH, then one week later prostaglandin. The new twist is that instead of 48 hours after prostaglandin, 56 hours later we give GnRH and then breed 16 hours later. The traditional presynch/Ovsynch was prostaglandin, 14 days later prostaglandin, 12 days later GnRH, 7 days later prostaglandin, 48 hours GnRH and then breed 16 hours later. There are some real advantages to this new 56-hour one that theoretically make sense—in a practical sense we are seeing some good results.

How consistent are you with the increase in pregnancies?

The increase in pregnancies that we see is about 8-10 percent increase and if this holds true across the herds as more herds pick it up, it is going to be really encouraging. This eight-hour expansion in the window between times of GnRH allows for a little bit larger follicle, so more mature follicle, that we are ovulating. It does theoretically make since. The first study was done by Milo Wilbank at University of Wisconsin, one of his grad students had 300 cows comparing against the traditional 72 hour cosynch to the 56 hour GnRH interval, and again 8-10 percent increase is what we’re looking at. There are not many things we can do to get this kind of increase when we’re talking about synchronization. The critical thing too is that the second interval between prostaglandin and GnRH—many individuals, dairymen, have gone to 14-14 for convenience to have the same day of the week. Research has shown 12 days prior to the start of Ovsynch is critical so that we can rescue some of those follicles before they die and undergo atresia. So that 14-12-7-56 is a pretty critical time interval if you want to optimize the synchronization protocol.

Thank you, Ray. That’s Ray Nebel, senior Reproductive Solutions specialist at Select Sires.