Ask any dairyman what he wants from
semen, and he will say “more milk”. But
ask what bothers him most about his herd, and he will say “cows don’t last long
enough”. Increasingly, we are
recognizing that the source of “longevity” in cows is to pick from
longer-functional life ancestors.
If you were to compare this
pedigree to most AI young sires, you would find the typical dams only show one
lactation—a big 2 yr old record that set up a high index, after which the cow
enters ET flushing. No later lactations
are ever shown—most such cows never calve but once, thus are unable to prove
they own any genetic capability to function as you would ask them to do in your
herd. If this a multiple generation
pattern in the pedigree, the lack of proven longevity can turn into a lack of
the genes to support functions that you need your cows to have. Think about it. Where did short herdlife cows come from
anyway?
PTA indicators related to selection
for longevity:
Cow fertility rate (DPR) General health (SCS) Will to live (Stillbirths) Months in production (PL)
None of these actually address all the
factors (including type) that would influence selection to improve
“longevity” (the ability of a cow to
remain productive and functional into mature ages).
For any cow to perform as these do,
they have to have the basic fertility to breed back, the stamina to survive
calving and thrive in milking, breed back again, calve again, milk some
more—all the while functioning in an environment (walking on concrete, getting
in and out of stalls, competing at a bunk, hot or cold weather notwithstanding,
sturdy legs, healthy udders, and a strong will to live). This is the pedigree we are seeking
to make your job easier. The type score
ages reinforce the production record.
Cows must possess youthful and
correct type to gain or maintain EX scores at mature ages.
The way to find the “outlier” bull is through his pedigree
In spite of all the excitement over Genomic potential, dairymen are starting to realize that it does not provide any new information— nor can it insure accuracy of any individual’s genetic evaluation.
Genomics does not replace what we can learn from a careful review of the full pedigree of available sires. Unfortunately, fewer AI systems deem it important to provide this useful information. Pedigrees contain the clues to successfully breeding for longevity. Some of the deepest maternal pedigrees in AI can be found at Taurus, Foundation, International Protein and Excalibur Sires.
If your goal is to breed cows that last longer, no
one can help you more than we can.
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