Recently published USDA data from 2012 DHIA herd
reports indicates that high culling rates continue to plague the dairy farmer’s
income and equity statements. While
culling dairy cows when beef price is higher than normal is an aid to cash
flow, the cost of raising heifers depends on feed costs (which are high enough
to inhibit growth in the beef cow sector).
The simple math is, every time you turn a cow into a cull and have to replace her, your
equity takes a $1000 “hit” (the market difference between culls and
replacements today).
Turns out that Holsteins have
replaced Guernseys as the breed with the shortest “Productive Life”. On 2012 data, this is how each major dairy
breed “ranks”:
Breed Cull rate Breed Cull rate Breed Cull rate
Holstein 32.7% Brown Swiss 29.8% 3x crossbred 26.9% Red
& White 32.0% M Shorthorn 28.6% 2x crossbred 26.1%
Guernsey 30.8% Ayrshire 27.7% Jersey 24.9%
Is crossbreeding the answer
to improving cow turnover?
The data seems to suggest it, IF you ignore the obvious: (a) Jerseys
are still better for herdlife than crossbreds;
(b) crossbreeding beyond three generations is
usually accompanied by a loss in milk volume;
(c) Heterosis response [hybrid
vigor] is greatest in the first generation, but declines with each added
generation in which the same trait index is used (regardless of breeds
added). Thus crossbreeding
alone does not replace gene trait selection IF your goal is to
improve herdlife while maintaining or gaining on per-cow production.
Does selection on “health and fitness traits” work?
According to a recent article in Holstein
International the low point in Holstein fertility levels was hit in
2005. Since then, the average DPR
(“daughter pregnancy rate”) of AI preferred sires has risen. But so far, on the 2012 data above, Holstein
cows still leave herds 30+% faster than Jerseys.
How much of the Holstein disadvantage is due to
lower fertility rates?
Keep in mind the commercial
breed average for crossbreds as well as purebreds in any breed still show
the “average” cow and “average” herds only get three lactations per cow. Dairy profit margin over the cost of
replacements would increase by 25% just by getting one more lactation per
cow. Longevity is a
heritable characteristic, thus a breeding program seeking longevity will pay
dividends in profitability.
The most important trait in
selecting for longevity is clearly fertility. Cows that do not rebreed do not
stay in our herds. Biological
research in many different species clearly shows that fertility and a will
to live are strongly correlated.
Thus selecting for better fertility will contribute to lower stillbirth
rates and is linked to general health qualities in your herd.
How much of the Jersey advantage over all other
Breeds is due to inbreeding?
What you really want to know is,
“will this computer mating program that adjusts for inbreeding save me from
shorter Holstein herdlife?” – and the answer is clearly NO. In fact, the Jersey breed is the
most “pedigree inbred” of all major dairy breeds, yet it remains the longest
productive life breed.
Holsteins as a whole are 25% lower
in average pedigree inbreeding (ibc%) than purebred Jerseys.
(continued—how much is due to inbreeding?)
No computer sorting program
leading you to the lowest “efi%” matings has ever been proven by
any University study to work.
“Avoiding Inbreeding” when all AI sires in every Genomic breed are fast
becoming closer related than ever before is a marketing ploy rather than an aid
to herd improvement.
This is why we continue to urge
you to give the “aAa” Breeding Guide a try. The proven solution to avoiding “inbreeding
effects” is to recognize that a stronger, well-balanced physique avoids
expressing “inbreeding depression”. Trait
selection on health and fertility traits associated with the problems of
inbreeding will then synergize with the “aAa” mating to avoid producing
“inbred” animals.
How much of Holstein herdlife is due to size?
Not as much as all the dialogue criticizing
registered Holsteins would suggest.
Holstein USA studies are showing that the purebred Holstein has been
gaining size at the rate of 25 pounds per generation.
If your facilities were built in
the 1970s and you have not changed anything, today’s cow is likely 240 pounds
bigger than the assumptions of your cow facilities (10 generations x 24 pounds/
generation).
But if you built fairly recently,
your building design would handle the larger cows of modern breeding.
USA type data is hampered in that
it only measures “stature”. Canadian
type data measures both size (weight) and stature (height) and their trend
lines may reveal the real problem:
1991 to 2001 birth dates: average stature of first calf
cows gained 5 cm (approx 2 inches)
average weight of first calf
cows lost 7 kg (approx 15 pounds)
1996 to 2001 birth dates: average stature of
first calf cows was virtually unchanged; however
average weight of first calf
cows lost 21 kg (approx 46 pounds)
Basically, the near-universal
preference in classification for a more angular frame (more tall
than wide, more lean than fleshy) is producing new cows that are actually lighter
in mass, are less sturdy on their front legs, have less muscle control over
rear legs, have softer feet, than the sort of physique that gave their maternal
ancestors a full productive lifetime.
Again, the real causative
problem is a lack of “balance” in genetic selection. On the trait selection side,
AI studs always preferred milk volume over component density, alongside earlier
maturity of the production capability, with the result bigger heifers
make the most milk. Selection
sets these trends.
It is disingenuous to blame breed
type classifiers for problems that started from index rank selections.
The system they are using (linear
trait scoring) was a product of the 1970s University view of “type” based on
what sort of first-lactation cow produced the most milk volume. This was a radical change from the breeder-developed
type descriptions that were focused on cow longevity under forage feeding.
Tell me how to rise from “average” to “exceptional”
If you wish to produce cows that
have balance between “tall” enough and “wide” enough, use “aAa”.
If you wish to produce cows that
have balance between “strength” and “dairyness”, also use “aAa”.
If you have herd issues with SCCs,
fertility or component% levels, the PTA trait data is there to
help.
Keep in mind that PTAs for Productive
Life contain assumptions that may not fit your environment.
Thus while “PL” may help you avoid
short herdlife cows, you need more information to gain herdlife.
Look for evidence of longevity in
the maternal lines behind bulls you are considering.
It seems like every “expert” today is picking on the
Holstein.
However, it remains true that 88% of the dairy cows
in North America are “Holsteins”.
Only 5% are crossbreds, 5% are Jerseys, and 2%
represent other traditional breeds.
Thus the productivity and profitability of the
Holstein cow remains essential to dairy industry survival. Holstein breeding must provide the genes
to turn around negative trends that have led the Holstein to the shortest
average herdlife in breed history.
Inside this newsletter you will find some recent
facts and figures that we hope will add to your perspective of your
opportunities and exposures in Holstein breeding.
You might also ponder this idea: you can create “outcross” hybrid vigor
within any breed if in the next generation you pick your sires in a different
way. Different trait patterns
require different DNA genotypes—and crossing different genotypes is how we
stimulate a “heterosis” response to improve all “vigor” traits.
Mich Livestock Service,
Inc ** For the Best in Bulls ** ph “toll
free” 1 (800) 359-1693
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