Select Sires

Ten Priorities of Reproductive Success
(Part Two)
Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired Oct. 2, 2003
With Dr. Mike O’Connor, Dairy and Animal Science Extension,
Penn State University

Today’s reproductive moment is with Dr. Mike O’Connor of Penn State Dairy and Animal Science Extension. We’re continuing our discussion from last week: The ten priorities for reproductive success. Last week, Dr. O’Connor, you advised to feed a transition ration that maximizes feed intake and minimizes postpartum problems. You also touched on a clean-dry maternity area to prevent metria, mastitis, and delayed conceptions in the area where they are likely to begin. And, you also advised making the voluntary waiting period a critical control point. This week you start off with observation – mingling with your herd.

Heat detection is always a challenge to dairy producers. The primary sign of heat is standing to be mounted by another cow. Research has shown that anywhere from five to 15 percent of the cows bred in this country are not in heat when they are inseminated. The challenge is to get employees, or the herd manager himself, out to mingle with the cows to see if these cows are exhibiting heat. That way, fewer cows are bred on secondary signs of heat, which have been shown to reduce conception rates. So, getting out and mingling means getting out and observing the cows. Now, on larger herds this has become a tremendous labor challenge, and some producers are going to timed breeding programs and estra-synchronization programs. Or they are using pedometers, if they are building a new milking parlor and are integrating pedometry into the system. We know that cows are much more active when they are in heat, and these systems have been shown to be effective if they are used correctly.

Setting up a standard operating procedure for heat detection is important as well.

Yes. We are not able to change the cow’s physiology at all, so we have to change our management and make sure things are done in a systematic fashion. I really like to stress to dairy producers that there really has to be a systematic approach today in reproductive management. So, an SOP should be posted where everyone can see it and understand it, so that heat detection and proper timing of insemination is done routinely, on a daily basis. If it isn’t, cows are going to slip through the cracks and have delayed conception, long days open and low pregnancy rates.

Any advice or additional information on what to use as heat detection aids?

Well, if someone is in the expansion mode and building a new facility, a new milking parlor, or looking for software programs, then pedometry may be a system they might consider. It would be automatic, but it is not foolproof. In addition to that, a simple method that has been used over the years is marking tail heads with crayon marking, and then looking to see if the crayon has been removed by cows mounting one another. The problem with that method is that you will probably identify the cows that are in heat, but you will probably suffer a lower conception rate. But, some dairy producers with large herds have to rely on something, and they have gone to that system. K-mar heat detectors have been used for many years, but a lot of these are false-positive. Therefore, it should be used as an aid to observing the cows, which should be the primary focus–getting out and watching heat. But if you cannot get out and mingle with the herd, then unfortunately you have to rely on some of the mechanical methods.

That is Dr. Mike O’Connor of Penn State Dairy and Animal Science Extension. We will conclude our top-ten priorities of reproductive success on next week’s Reproductive Moment.

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