Performance Line
Invest in the Genetic
Future of Your Herd
By Tonya Amen, National Center for Beef Excellence
EPDs are the best estimate of an animal’s genetic
worth as a parent and as such, are the preeminent
selection tool available for selecting seedstock.
EPDs for each trait are the best selection tool
because all available sources of information on an
animal are included and properly weighted; this
includes performance data on the animal itself (if
available) and all progeny, pedigree relationships,
and genomic results. Boiling down these sources
of information into one number takes the guess
work out of trying to decide how to weight each
piece of information, plus EPDs have the ability
to make use of genetically correlated traits to
improve the accuracy of selection even when a
trait hasn’t been evaluated in the animal itself.
Pedigree - For many decades, breed
associations have been tasked with tracking
pedigrees for registered seedstock. In more
recent years, the pedigree has been used to
form the initial estimate for animal’s EPDs.
Performance Data - Also known as
phenotypes, these are the weights or measures
collected and reported by a breeder along
with appropriate contemporary groups.
Contemporary groups are a set of cattle of
the same gender who are managed alike.
Care should be taken to only report actual
measurements for each trait. “Guesstimates” and
rounded numbers (for instance rounding to the
nearest 5 pounds for the weight traits) removes
accuracy and genetic variation from the EPDs.
Genomic results - Results from DNA trait tests,
also sometimes referred to as genomic results,
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are also included in the genetic evaluation.
Genomic results have value in genetic
selection when used with all other available
performance data and pedigrees. In order to
insure the most accurate use of genomics,
it’s important to test both genders as well as
those from all strata on the performance scale
(the good, the bad, and the ugly). Testing a
wider variety of animals instead of just the
lead bulls in a sale will improve the efficacy of
genomic testing for the entire breed. Currently,
NALF breeders have tested far more bulls
than females. Females are often the basis for
your herds going forward (many of you sell
your bulls), so I’d encourage you to consider
investing in the genetic future of your herd.
For each trait, EPD values are presented in units
of the trait and reported with an accuracy,
which allows breeders to judge how much
information is behind the EPDs. This allows
seedstock producers and commercial cow-calf
producers alike to rank genetic merit of animals.
Most commonly, this tool is used to select sires
for economically important traits, but through
the use of genomic technology and advanced
reproductive technologies, these days even
females can achieve much higher levels of
accuracy than ever before, thus allowing quicker
genetic progress for traits of importance.
Online tools are available to find Limousin and
LimFlex sires and dams to meet the genetic needs
for every kind of operation. Using the search tools
available online at https://limousin.digitalbeef.