Performance Line
Pedigree
Genomics
GE-
EPDs
Performance
Data
Progeny
Figure 1: BOLT-powered EPD components
Currently, there approximately
1.4 million birthweights, 1.0
million weaning weights,
and just over 440,000 post-
weaning gain records being
used in the NALF national cattle
evaluation. In other words,
about 61% of the animals
in the evaluation have BW
records, while only 19% have a
record for post-weaning gain.
It’s very important that
these weights are accurately
measured and reported in
pounds without rounding.
If you’re using tape-weights,
for birthweights, we would
like for you to let NALF staff
know so that the appropriate
variance structure can be used
when incorporating those
weights into the evaluation.
14 | MAY 2019
Currently ultrasound records
are used as correlated traits for
their respective carcass trait. For
each ultrasound measurement
used in the evaluation (ribeye
area, intramuscular fat, backfat),
there are +/- 60,000 records.
For the respective carcass traits,
there are only between 6,500
and 7,000 records for each
trait (carcass weight, ribeye,
marbling, and backfat). I think
it become apparent, that a
discussion within the breed
about how to collect more
pedigree-identified carcass data
for use in carcass EPDs would
be a good use of resources.
In addition to classic pedigree
and performance data, genomic
profiles provide another source
of information that gives an
earlier indication about the
genetic merit of tested animals.
While valuable for all traits
of interest, genomic tests are
especially helpful for those
traits in which the animal itself
will never have a phenotype
(like carcass traits), or traits that
take many years to measure
(like Heifer pregnancy or the
longevity of a bull’s daughters).
Currently, less than 0.6% of
the animals (about 14,000 hd)
have a genotype being used
in the evaluation. Due to the
increased impact of genomics in
the current genetic evaluation,
it’s really important to have
genotypes on a representative
cross section of the breed both
in terms of gender (testing
bulls and heifers), as well as
genetic merit (testing the
bottom end as well as the top).
In order to move the Limousin
breed forward into the future,
we must arm registered and
commercial breeders alike with
the most powerful and accurate
tools to meet their selection
goals. The backbone of these
tools starts with making it a
priority to collect and submit
as much accurate performance
data as possible and to augment
this with a genomic testing
strategy that includes both male
and female animals across the
spectrum of anticipated genetic
worth for the various traits. We
have the technology to make
rapid genetic progress possible,
let’s make sure we have the
data to ensure its efficacy. I