Page 10 - AWA Vol.42-No.1 issue

DAIRY FARMING

Smart Breeding Doubles the Benefits of Genomic Testing

Farmers who make breeding de-
cisions based on genomic testing
achieve greater genetic progress.
But genomic testing becomes twice
as valuable when the results are
used to sharpen selection of breed-
ing animals.
Breeding values twice as reliable
Determining breeding values for a
calf only a few days old, at a high-
er reliability than for a cow that has
calved four times, is now possible
with CRV’s genomic testing. These
tests provide information on breed-
ing values for more than fifty traits,
and give direct insight into A2A2 sta-
tus, polledness, and hereditary de-
fects. Parentage can also be verified use genomic breeding values can more cows to be bred to beef bulls.
through genomic testing. reliably select the animals that best This raises the selection pressure
“Since genomic testing was intro- match their breeding goals. Genom- and speeds up genetic gain even
duced roughly fifteen years ago, re- ic testing also enables more precise more.”
liability has increased significantly,” mating decisions,” he adds. Jonas supports his advice with re-
explains Jonas Perneel, information Sharper selection, faster progress sults from a study by the Universi-
solutions specialist at CRV. The reli- “By using animals with the highest ty of Wisconsin-Madison. The re-
ability of genomic breeding values breeding values for breeding, rapid search calculated genetic progress
now exceeds 80 percent for many genetic progress can be achieved, for the U.S. economic index Lifetime
traits. That is far higher than the reli- especially if the lowest-ranking an- Net Merit (profitability over a cow’s
ability of traditional pedigree-based imals are excluded from breeding lifetime) when selecting based on
breeding values, also called ex- by inseminating them with a beef expected values versus genom-
pected values. Table 1 shows the bull,” Jonas continues. “Farmers can ic breeding values. The results are
reliability of expected values versus accelerate progress even further by shown in figure 1.
genomic breeding values for several using sexed semen on their very
key traits. “For most traits, genom- best animals,” he adds. “Sexed se- Genetic progress doubled
ic testing doubles the reliability of men produces heifer calves from "The results clearly show that se-
the breeding value,” Jonas empha- the top animals, and ensures enough lection based on genomic breeding
sizes. “This means that farmers who replacement heifers, which allows values produces greater genetic

Figure 1 – Genetic progress for Lifetime Net Merit when Table 1 – Difference in reliabilities of expected values and genomic breeding
using expected values and genomic breeding values at dif- values for important traits
ferent levels of crossbreeding (source: University of Wiscon-
sin–Madison).

8 Vol. 42 No. 1