ReSynchronization Programs

Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired Nov. 30, 2006
With Ray Nebel,
Senior Reproduction and Herd Management Specialist, Select Sires Inc.

This week, Ray, you’re talking about resynch protocol.

Yes, Bill. I think there have been some very good protocols looked at and an extensive amount of research for first service. Our presynch-ovsynch protocols that we have talked about in the past have been researched at a number of different universities and probably hundreds of different herds. To follow up on that, the the next 21 days, the next cycle, is critical. If we do get 35-40 percent of the cows pregnant off the first cycle, the back side of the coin is that we are going to have 60-65 percent of cows that we still need to get pregnant. So resynchronization protocol is critical. Traditionally what we have done is just heat detection, either with tail markings or visual, to hopefully catch the next 21 days after the first service presynch-ovsynch so that we can catch those repeat cows. But in today’s large herds with high milk production, that just hasn’t gotten done. The resynch protocols, the most common one is to start at 32 days after first service and to give GnRH seven days prior to that, so 25 days after breeding, to come in and give cows that haven’t been inseminated after that breeding window 18-24 days, to give those cows a GnRH injection and then seven days later they will be palpated for pregnancy either by ultrasound or rectal palpation. At that point if they are found to be open, give them an injection of prostaglandin and then 48 hours later they can get prostaglandin and then 16 hours later timed AI. So just by giving GnRH seven days before, right outside the window, so we do our normal heat detection, which cows should be returning 18-24 days after breeding. The next day, on day 25, the cows that we haven’t detected in heat and inseminated, they would get GnRh one week later; we’d do our pregnancy exams so those open cows at our pregnancy exams are now set up for prostaglandin and are going to be bred three days later. After a prostaglandin at preg check, and then 48 hours later GnRH, and then 16 hours later insemination. So three days after we determine the cow is open, we have semen back in her so that by 35 days all cows that were inseminated are reinseminated either by natural heat, 18 and 24, or by resynchronization. By far this is the most used resynch program. Again this was developed up in Wisconsin, this time Paul Fricke and his graduate students at the University of Wisconsin developed this resynchronization protocol. There are some new ones coming out that hopefully we can talk about next spring, where they use a CIDR device that goes in to reset the cycle of the cows. That one might be a little bit early. We are doing some research and many others are doing research on inserting the CIDR for resynchronization; but today for herds that want to get that second service in there for a timely manner, this is the bread and butter for what we see out there in resynchronization.

Thanks, Ray. That’s Ray Nebel, Select Sires reproductive management specialist.