Thursday, May 27, 2021

Which cow needs to be more feminine? (Dairy? or Beef??)

  CONCEPTIONS Beef Cow Calf Newsletter                             Sept-Oct 2020 

Given I have been analyzing “dairy” cows for decades, under the “aAa/Weeks” service mark (both purebred and crossbred), but recently have also studied many more beef cows in cow-calf herds, some observations are telling me that trends in each are following parallel lines.

High production dairy herds are losing natural fertility quality as they select in the direction of “performance traits” geared to corn-based (as opposed to hay-based) feeding.     Visually, such cows are built more like steers, having lost the femininity we correlate with sound reproduction.    More and more, such herds are utilizing “ov synch” protocols that include early-lactation hormones to complete uterine recovery from calving.    

There is no “production” without prior reproduction.    “No live calf = no income” is pretty clear to most beef cow-calf producers, so in the purebred breeds we are as cognizant of needing “maternal trait” cow/sire lines (“momma instinct” cows who are easy breeding, easy calving, good milking) as we are “performance” sire lines (for faster growth calves and post-weaning weight gain). 

Feminine qualities in our momma cows will lead to more live calves, because their own will to live matches the instinct to get up and take care of a newborn calf.   In physical structure you have wider hips, open pins, deeper flanks, and wide-sprung ribs-- all of which not only accommodate easier calving but indicate capacity to eat forages from which the needed milk will come in desired volume.    Feminine cows are better at cycling and conceiving, because their glandular production of reproduction hormones is in balance.

It is an oddity that in the dairy industry, so many have lost sight of these biological qualities and visually-identifiable characteristics.     But dairymen are easily fooled by high-peaking cows during her “fresh” post-calving days, the highly angular rack of bones cow that puts away all the grain you can feed her and just makes milk.   You can design cows like that from high-performance milk bulls, and then struggle to get them bred back in a timely manner so that future production is insured.  

The common weakness in “E P D s” (beef) and “P T A s” (dairy)

The Dairy industry after World War II began to embrace “scientific” (population genetics) breeding, developing “predicted transmitting ability” measures for all major traits (lactation pounds milk, butterfat, protein) and theorizing all sorts of broad assumptions about all other desired selection qualities (“higher milking cows will still breed back ok, have calves ok, live a normal lifetime”)—assumptions that, on later data after several generations passed, proved to be untrue.

The Beef industry within twenty years of Dairy also fell into the hands of number crunching population geneticists, who told us we could identify the faster growth, heavier weaning, heavier finishing genetic sources strictly from data, and the EPD era was born.     The Angus breed, alongside the newly imported continental Euro breeds (with frames equivalent to the larger dairy breeds), were more aggressive in utilizing this data in sire selection.

Today, in both Beef and Dairy AI, you have premium-price sires that are selected through DNA (“Genomics”) imputations, where actually measured EPDs from real measured performance may be three or more generations behind.    It gets to the point where the ET donor dams never have their own calves (because they are “too valuable” to risk to the rigors of calving, milking and rebreeding annually)…

As a result, you may start to see females in Beef breeding circles who no longer look “feminine” --  they are more like steers in their physique.     When this starts to happen, in the following generations you may start to see cows that act like steers, have more difficulty calving (from tighter, more “masculine” pelvic sizes) and have less interest in mothering their calf, are harder to catch in heat, and as difficult to conceive (because they lack the more even body-conditioning ability of the well-sprung, deep-rib grass-based physique with its superior forage digestion).

Visual trait selection remains important.

Dr Jan Bonsma, among other seminal thinkers in the Beef industry, observed that “It takes a properly masculine bull to sire properly feminine cows.”     This is the sort of knowledge that never changes, as breeding fads come and go.    Nothing is more frustrating in cow-calf than trying to make calves from “steer cows”.

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