Wednesday, January 6, 2021

What defines the elite club-calf bull?

 From the Jan/Feb 2018 CONCEPTIONS Beef Newsletter

In recent years, it has become harder for new young sires to break into the club-calf scene.    The famous old bulls, many of whom now have restricted semen producing capability, still have a strong hold on people’s imaginations.


Of course, the obvious consequence of this is that prices for “name recognition” sires have dramatically increased in the last two breeding seasons.


Are these premium prices justifiable?


Marketing Consultants (such as Travis Mitchell of Pandora Cattle Company, near us at Laingsburg MI) say “Yes”.     Tracking the sale value of prospect calves at fall club sales, the premium the progeny of “name” bulls bring appears to more than recover the incremental semen costs.


However, some basic biological principles of phenotypic mating suggest that the bulls who produce the best “steer calves” do not produce the same quality of breeding females, and half the genetics of your best calves is that momma cow who birthed and nursed them.


Just as with crossbreeding, the tool you hope to harness is “hybrid vigor”, the response to a heterosis mating.     At conception, two genotypes (Sire + Dam) combine by a re-pair-ing of genes attached to each chromosome.   Half the sire’s genes are discarded; half the dam’s genes are discarded; the calf you get is a genetically unique recombination of those two genotypes.


Basically, take a cow that already looks like a club steer, breed her to a top clubby bull, and you might get a train wreck instead of a winner.    In fact, the biggest issue with cows that look like steers is their lower fertility response.    We are seeing a gradual increase in “late” calvings from AI rebreedings that occur in herds where the cow herd has accumulated steer/performance genes while losing cow/maternal genes.   


Analyze the phenotypes of your cows


Most of you seem to have a system for matching your new bull selections to the cows you are calving next spring.     As for yearling heifers, “calving ease” considerations produce a second bull list, and we often observe that the best new replacement heifers come from those matings.    This is because there is a correlation between calving ease and maternal qualities—while the premier steer sires often sire much heavier boned and fuller front ended calves, not as amenable for birthing from heifers.


Data I presented to you a year ago showed that of all the measured Beef breeds in play in the USA, by far the hardest-calving bulls are the “Club calf” bulls.    By contrast, breeds that emphasize range ability (growth rates on grass, efficient milk production, heat and cold resistance for living outside) also seem to have sorted out the harder calving lines that might prevent a successful unassisted birth.


Even in beef cattle, there is more variation within each breed than differences between breeds.  This is why it is generally not safe to assume “He’s an _ _ _ _ _ bull, therefore will be easy calving” or  “She’s a _______ cow, therefore easy fertility”.      All individuals are unique gene combinations.

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