Tuesday, January 25, 2022



In both the Dairy and the Beef world, the “establishment” of corporate research and university extension continues to promote “data driven” genetic selection, now utilizing Genomic indexes developed from computer analysis of trait patterns and associated DNA markers for the cutting edge of cattle breeding.     Feed, seed and chemical companies cheerlead for these approaches, as experience tells them their sales go up alongside the adoption of linear trait selection.

What constitutes a profitable cow-herd ?

At the basis of optimized Beef production is maximized reproduction.     A cow herd that gets its reproduction maximized, is a group of cows that (a) Conceive on time for desired calving dates; (b) Birth live calves with no assistance;  (c) follow their maternal instinct to get up and lick that new calf to life, urging it to stand, coaxing it to nurse;  (d) stimulate lactation at a pace that the calf will utilize;  (e) sustain body condition from a vigorous appetite so as to repeat this cycle all over again for the next season.

How often do we confuse performance with maternal cow-calf ability?

Too often, in our Performance-driven measurement systems, we give more credit to the bulls siring the heaviest weaning calves, than the cows giving those calves their start in growth.   In earlier days, we made clear distinctions between “Performance” sires and “Maternal” sires – using both at a 2/3 to 1/3 ratio so as to maintain adequate replacement heifers in the cow herd.

What follows in data-driven systems, is that cow (sired by a name-recognition “performance” bull) that weaned an 800 pound calf one year gets a pass for not getting rebred on time for the following year, her Genomics giving her a “superior” label even though she does not have the balance in character or behavior to do the job in every year.     These are often the cows who become dedicated embryo donors: they have that “bully” performance phenotype, grew one great calf (without carrying her next calf on time) and then the “numbers” seduce us: we need to propogate this “high genetic value” cow.    Is she likely to produce heifers that will make a sound, annually calving cow, when she could not do it herself?

Sorting out the breeds by their embrace of data-driven evaluation

You rarely see this happen in the breeds closer to “heritage” status, where you also find many breeders pursuing “grassfed” beef (raising calves on cows that graze grass, and finishing steers on high-energy grass and summer annual combinations) and seek to capture price premiums that have developed for leaner, naturally marbled meat.     It is a “feedlot” disease, in which we select on larger frames, associated with higher post-weaning gains as long as corn is the focus of the bunk ration.      These in effect, have linked “feedlot adaptation” to “genetic value” and the data (expressed in pounds, in linear measurement) supports the conclusion, without really referencing the costs of reproduction, health, and feed cost per day going into this paradigm.   

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