A cow with her calf.

New Evaluation Traits for Dairy Cattle

Evaluating dairy cows by how easily they give birth—and how quickly they become pregnant again—is the newest information resource that Agricultural Research Service scientists are providing to livestock breeders to help them improve their operations.

The first national genetic evaluations for cow fertility, called "daughter pregnancy rate," provide dairy cattle breeders with a tool for achieving desired levels of reproductive performance in today's milking herds. The term "daughter calving ease" reflects the ability of a particular cow to give birth easily. Dairy producers and breeding companies use that information when choosing and mating bulls and cows to reduce expenses caused by difficult births.

This data—and much more—is being offered by the ARS Animal Improvement Program Laboratory (AIPL) in Beltsville, Md. The lab's vast data collection helps dairy farmers produce the healthiest and most productive cows possible. AIPL information has helped U.S. dairy breeders increase individual animal yields to record levels. As a result, U.S. milk production has increased even though the number of dairy cattle has declined.

AIPL research leader H. Duane Norman oversees a database that includes many important yield traits as well as fitness traits that affect health, vigor and profitability. For example, the database includes information on mastitis resistance, reproduction, fertility and longevity.

Tracking these factors is important because dairy farmers rely on the information for breeding purposes. AIPL scientists estimate the genetic merit of thousands of bulls and millions of cows from data collected since 1960 through an industry-wide dairy production testing and record-keeping system, and through breed registry societies.

This vital information has been used as the basis for matings to improve the next generation of U.S. dairy cows. The evaluation traits are used by 38,000 U.S. dairy breeders, numerous artificial-insemination organizations, extension specialists, dairy records processing centers and dozens of researchers here and in other countries.

By becoming ever more efficient, dairy producers not only meet consumer demands, but make a profit as well.

ARS is the U.S. Department of Agriculture's chief scientific research agency.