Select Sires

Calving Ease
Part One
Transcript of Select Sires' Reproductive Moment Program
on DairyLine Radio Which Aired June 10, 2004
With Chuck Sattler, vice president, progeny testing,
Select Sires Inc.

This weeks’ Reproductive Moment is with Chuck Sattler, vice president, progeny testing at Select Sires and our topic calving ease.

Chuck, just how much of a problem is calving difficulty on dairies today?

Data from the NAAB genetic evaluation shows that difficult calvings occur about eight percent of the time in heifers and about three percent of the time in later lactation cows. These difficult calvings cost money because they reduce the survival chances of the calf, and cause poorer reproduction in the cow, as well as reduced production in the cow. These losses all add up. In research done by Iowa State University, they looked at DHIA records and compared them to cows with different birth difficulty scores and found that it costs about $230.00 for every time a difficult calving occurs. Interestingly enough, about two-thirds of this loss is due to on-going reproductive problems in the cow following the calving as well as longer days open in that cow.

How can producers manage calving difficulty?

Well, the most important factor is good solid on-farm management of replacement heifers. It is important to have the heifers well grown and to make sure that they are not over conditioned at calving time. The heifers also need to be bred on-time so they are not too old when they calf. Monitoring of the calving process is important, as well, so that small calving problems do not turn into big ones. Another factor, in addition to management, are the genetics of the cow that is carrying the calf, as well as the calf being carried. They play a role as well in determining whether the birth is an easy one or a difficult one.

Well, since genetics are a factor, can producers choose service sires that reduce difficult calving?

Yes they can. One of the key benefits of using proven A.I. sires is that we have information about the genes they transmit in regard to calving ease. The USDA calculates these updated genetic estimates twice a year. They provide two values: one is called service-sire calving ease, and this indicates how easily calves of the bull are born. The other is called daughter calving ease, and this indicates how easily the daughters of this bull will deliver calves when they mature and reach that point in their lifetime. These values are expressed as a percent difficult birth. For both service-sire calving ease and daughter calving ease, the average value for A.I. sires is eight percent with a range between four and 14 percent. These values are routinely available to dairy farmers from A.I. organization Web sites, as well as marketing materials provided by A.I. representatives.

For more information you can contact a Select Sires Reproductive Solutions™ specialist, they are there to help you.

We will continue next week on our discussion of calving ease with Chuck Sattler, vice-president of progeny testing at Select Sires.

™Reproductive Solutions is a trademark of Select Sires Inc.

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