Sports fans compare teams by power rankings. Now the beef
industry
has a statistical ranking system, too.
“Instead of teams, we have animals,” said Keith
Bertrand,
a University of Georgia animal scientist who helped develop the
ranking system. “It’s a way for breeders to compare animals
and find out what bull has the potential to pass the best
characteristics
on to offspring. Bulls with the best numbers will be more popular
for breeding purposes.”
Consumers are the real winners in this new process because
the models help breeders select which steers are most likely to
yield lean, tasty, well-marbled steaks.
Using high-powered computers Bertrand, and other animal and
dairy scientists in the UGA College of Agricultural and
Environmental,
analyze and evaluate millions of animal records to generate
rankings.
The rankings are then used to develop models that predict
possible
outcomes for the beef industry.
“Our models are similar to weather forecast models,”
said Bertrand. “We try to predict the future.”
Livestock breeders can compare values for 15 genetically
linked
characteristics, such as those that indicate greater growth
potential,
leaner meat and other qualities important to growers and/or
consumers.
The bovine matchmaking models predict which bulls will produce
future generations with the desired traits.
“Producers realize this information means money, and they
use genetic evaluation to buy and sell bulls,” Bertrand
said.
The system, which evaluates 14 breeds of cattle in the United
States and Canada, is being expanded to include Central and South
American stock. The international ranking system will eventually
replace the U.S. National Beef Cattle Genetic Evaluation System,
Bertrand said.
Once a prize bull with desired genetic traits is selected,
a breeder can simply arrange to buy the bull’s germplasm – either
in the form of semen or fertilized eggs. If properly stored,
semen
for artificial insemination has a “shelf life” of two
to three decades.
Collecting genetic data on cattle is expensive and time
consuming,
especially when taking before and after measurements of animals
destined for supermarket shelves.
The UGA scientists pioneered beef cattle evaluations using
ultrasound, a less expensive alternative to other methods. Their
work has been funded by UGA Agricultural Experiment Stations,
the cattle industry, breed associations and the USDA.
The team
has found that ultrasound provides reliable measurements of the
amount of fat around the muscle, the size of the ribeye and even
the extent of marbling. In fact, research has shown that
ultrasound
measurements are equal to and in some cases better than similar
measurements obtained by USDA graders.
“By measuring yearling bulls and cows with ultrasound,
we can help breeders select for improvements in steers and
heifers
before they get to the slaughterhouse,” Bertrand said.
But neither scientists nor ultrasound can predict tenderness,
which results from a combination of age, breed, genetics and
muscle
characteristics.
“Tender is a hard quality to measure,” Bertrand
said.
“What does tenderness look like?”
UGA scientists are now working on methods to measure
tenderness.
Research strongly indicates there are bloodlines in each breed
that can provide tender beef. “Our goal is to find
them,”
he said. “Some day we may be able to use a blood test to
see if animals carry the genetic characteristics of
tenderness.”
(Photo 1. S. Bauer, USDA-ARS, Photo 2. J. Purdy, UGA
CAES.)
