Researchers Help Cattle
Breeders Optimize Profit and Desired Beef Traits
By Kathryn Barry
December 9, 1999
Tender steaks start with cattle
breeders who carefully document numerous characteristics of their animals. They
use this information to breed those animals with the best
combination of desired traits.
However, best has been a subjective and inconsistent measure,
according to Agricultural Research
Service geneticist Michael MacNeil. That slowed producers ability to
breed improved animals. Now, thanks to ARS research, breeders may refine their
decision-making by focusing on profitability.
MacNeil works at ARS Fort Keogh Livestock and Range Research
Laboratory in Miles City, Mont. ARS is the chief scientific agency of the
U.S. Department of Agriculture.
To assess their animals, breeders keep track of growth traits, such as
weights at birth, weaning, and yearling ages and at maturity. They also measure
carcass traits such as marbling and fat content that are indicators of value to
consumers. In addition, they record traits like the age when a female reaches
puberty, and her pregnancy rate.
Breed associations take the information, combine it with each animal's
genetic tree and run it through a computer program to develop an expected
progeny difference, or EPD. That lets breeders compare individual animals for
individual traits. They would know, for example, that cow A was more likely to
produce offspring with the desired marbling than cow B.
But the process is not complete. Producers were left with the difficult task
of combining the EPDs in an efficient manner. So MacNeil is improving the
performance testing process by using the EPDs to predict genetic potential for
profit. With his system, breeders will be able to know how to trade off changes
in fat thickness and marbling, for example, most profitably.
Breeders would also be able to rank animals more effectively. If there were
100 bulls for sale, breeders could rank them numerically to find the best bull
for their purposes.
The complicated calculations are not yet available in a simple computer
program for individuals to use. Producers will most likely get the information
through Cooperative Extension Service specialists or breed associations as the
lab passes on the technology.
This research is reported in the December issue of Agricultural Research magazine.
Click here to
read about it online.
Scientific contact: Michael D. MacNeil, ARS Fort Keogh Livestock and
Range Research Laboratory, Miles City, Mont., phone (406) 232-8213, fax (406)