Looking at “type” in
relationship to a cow’s productive functions
Both AI stud mating evaluators and Holstein USA type
classifiers use the linear trait methodology to categorize the functional
structure of the modern cow. Often
times, they do not agree on what that “perfect” cow should be physically, with
the AI stud view (joined by Genomic scientists) being that our modern Holstein
cow is “too tall” for commercial environments, while the Holstein classifier
and farmer breeder view is that they see too many fine-boned, deep-uddered
young cows they would not expect to live a full productive lifetime.
Scientists, who first developed the linear type
methodology in the 1970s and joined with AI studs to coerce the purebred breed
associations to adopt it for official breed type classification, now tend to
blame type classifiers for the cow faults in execution of the linear
concept. Meanwhile, breeders are
sticking with the idea that the higher scored “Very Good” and “Excellent” cows
will be the longer life producers, and object to the Genomic assumption that
“Good Plus” is the best type for commercial use.
Then there is the “aAa” view
The Weeks’
“aAa” Breeding Guide is used in both commercial and purebred settings, but has
never been officially endorsed by either side of the argument—thus tends to
function “under the radar” to help its users avoid being trapped in the fads
and fancies from theoretical science and traditional breeders that periodically
disrupt functional cow structure in popularly mated herds (using computer
mating systems or personal AI consultant mating).
In the Weeks method, the qualities of
the cow physique are assembled in an additive way, rather than in a preference
for linear extremes in a handful of target traits. Over my now twenty years as an approved
“aAa”
analyzer I would say that our
current type issue is the prevalence for “narrow” physiques,
which comes in part from the linear evaluation (by AI stud or breed classifer)
preference for “angular” cows.
How a lack of “width” translates into a lack of “functional cow”
You can start right with the fore part of the cow, that
linear concepts of the 1970s decided had no value:
the
head. 100% of the air she breathes, the water
she drinks, and the feed she eats has to enter the cow through the dimensions
of her head. If the head has a wide
muzzle, big round nostrils, and a wide sinus structure, she has a chance of
high performance. If she has a wide
forehead, there is room for the eyes to swivel in the skull and the brain to
work inside the skull. If the head is
proportionate in size to the body behind it, you will find that all the body
parts have more substance and function cohesively.
By contrast, too many linearly-selected heifers today have narrow heads,
small muzzles, weak jaws, slits for nostrils, and spend too much time panting
around the water tank any time heat or humidity rises. In any stress situation, the narrow skull
squeezes the brain and limits the range of her eyesight, producing a nervous
cow. Cows with narrow heads have less
inherent balance when on the move.
Correlations between narrow heads and narrow chests, slabby ribs, stiff legged stances
Stand in front of any narrow headed heifer. Do you see any front end capacity behind
that? Keep in mind that the heart sits in the center of the chest with the lungs aligned on
either side. The lifeblood in the cow
is circulated out to muscles by the heart, and the oxygenating of the returned
blood is performed by the lungs. Both
need chest room to fully function, the extension and contraction of both
takes room.
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