New Evaluation Traits for Dairy
Cattle By Sharon
September 25, 2003
Evaluating dairy cows by how easily they give birthand how
quickly they become pregnant againis 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
This dataand much moreis 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.