Select Sires

Putting Inbreeding in Perspective
Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio, Which Aired Nov. 21, 2002
with Chuck Sattler, vice president,
dairy progeny testing and genetic research,
Select Sires Inc.

This week’s Reproductive Moment is with Chuck Sattler, vice president, dairy progeny testing and genetic research with Select Sires. Chuck, today we are putting inbreeding in perspective. How much of a problem is inbreeding for today’s dairy producers?

Inbreeding can be a problem if it is completely ignored. On the other hand, if you have tried too hard to control it, you can maybe do more damage than good. Inbreeding is a very complicated issue, and because of that there are no real easy answers. It is something that can’t be ignored, but also can be over-emphasized.

The USDA has calculated inbreeding coefficients for dairy cattle. What are they and how can producers use this information?

Inbreeding coefficients are one number that USDA provides, and they provide those on cows and bulls. That number indicates the estimate of how inbred each animal is. The other interesting number that USDA provides on bulls is a value that predicts the amount of inbreeding this bull would cause if he is randomly mated to the current cow population. That is a useful number that indicates how much an outcross this bull really is. A typical number we see for these animals would be in the five percent range. We really can’t expect the bulls we are using today to produce zero percent inbreeding, but we should also try to avoid using these bulls so they don’t cause inbreeding in the 10 to 12 percent range.

In each percentage of inbreeding, how much is overall performance affected?

The estimate from research conducted by Virginia Tech University shows that for each one percent increase in inbreeding we probably would see about $23 of lost income over the lifetime of that animal. That doesn’t sound like a lot, but if we are increasing the inbreeding by five or six percent then we are getting into numbers in the range of $100. If you spread that over a herd of 200 or 300 cows, we see that it is an issue that can amount to some significant losses. So, we do need to pay attention. To balance that, we also need to be sure that we continue to use bulls that provide the balance of traits we need to produce profitable genetics while keeping the inbreeding level in check.

As we wrap this up, Chuck, what can producers do to control inbreeding in their herds?

There are three things that dairy producers need to do to monitor inbreeding:

They need to record complete identification on their animals. To control inbreeding we need to know the sire and dam of each animal and that needs to be recorded if any kind of control programs are implemented.
The next step is to use the computerized mating program. Several of these are offered in the industry. Select Sires offers Select Mating Service™. One of the key features of these programs is that they will look at the pedigree of the cow and compare it to the pedigree of the bull and try to balance the benefits of the genetic traits the bull offers with the degree of inbreeding that may be produced.
The third key point is that while we do try to monitor inbreeding we also need to breed cows we like, so we need to be sure that we continue to emphasize important traits and not get carried away to try to completely avoid inbreeding. In those situations the cure might be worse than the disease.

Thank you Chuck. Chuck Sattler, vice president, dairy progeny testing and genetic research at Select Sires.

Copyright 1996-2002 Select Sires Inc. Last updated 2-Dec-2002.

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