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DNA— The evolution
of livestock evaluation
Production agriculture has seen tremendous
technological advancements throughout history.
From the days of the single-bottom horse-drawn plow
to today’s huge four-wheel drive tractors that can top
500 horsepower, technology has increased our
production and efficiency like nowhere else on Earth.
Genetics Revolutionize Corn Production
In 1930, the average national corn yield was 30 bushels
per acre; in 1970, it was 70 bushels; and in 2009, it grew
to 164.7 bushels per acre. That is a steady increase of
1.6 bushels per acre per year since 1930. Some elite
producers have realized yields of more than 350 bushels
per acre! The National Corn Growers Association
attributes this increase primarily to improved genetics
and production technology. Over time, we have
significantly increased corn production and quality.
Progress in Cattle Production
In 1982, our national cow herd showed 50 million cows
producing 22 billion pounds of beef, for an average total
production of 445 pounds per cow. Compare that with
our cow herd in 2009 of 41 million cows producing nearly
26 billion pounds by carcass weight, for an average
production of 632 pounds per cow. We have increased
production, increased safety and increased quality
primarily through genetics and production technology.
For hundreds of years, visual appraisal was the only means
of predicting production. In the last century, we utilized
continued objective phenotypic observations and weight
recording as ways to describe differences in animals.
Estimated Breeding Values (EBVs) followed and ultimately
evolved into our current National Cattle Evaluation
expected progeny differences (EPD) system that today is
the best description available for all factors explaining the
potential production and quality in beef cattle.
Critical to previous EPD calculations was the need to
group cattle in sizeable, equal-opportunity contemporary
groups in order to show differences in individuals,
hopefully with similar management and environmental
inputs. Although the best evaluation at the time, it was
still dependent on parental contribution, and maintaining
large groups of like-managed animals.
Most Accurate, Dependable Information
Livestock evaluation and EPDs have finally evolved
to include the use of DNA as the most accurate,
dependable information to predict the actual merit for
quality and production of an individual. Today these are
known as genomic-enhanced, or GE-EPDs.
Pfizer Animal Genetics has formed a partnership
with Angus Genetics, Inc.
®
(AGI), a wholly owned
subsidiary of the American Angus Association
®
(AAA).
Bill Bowman, AGI president and AAA chief operating
officer, says, “This is part of our efforts to provide the
most accurate, most rapid genetic feedback available in
the beef cattle industry.”
Angus GE-EPDs powered by High-Density 50K (HD 50K)
from Pfizer Animal Genetics have been proven to show
a significant increase in accuracy and dependability,
especially in young animals. Depending on the trait,
the information from HD 50K may provide as much
predictive effect on an individual’s EPD as an animal
with up to 20 progeny records. (See Table 1.) This
means that just one HD 50K DNA test, when applied
to EPD calculations by AGI, provides as much genetic
information as more than a lifetime of production from a
typical cow, all before that individual is even weaned.
DNA Finds the Differences
As there are billions of possible combinations of DNA in
even full siblings, we have seen significant differences in
quality and production of flush mates. GE-EPDs are the
Some officials feel that our national
average corn yield may someday reach
300 bushels per acre. Can a national
average production per cow of
900 pounds be far behind?