I think a lot of people get way way way carried away with the redundancy of their selection protocols. By placing direct selection/culling pressure on TWO measurable traits, I can indirectly address all others.
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[*]FERTILITY: A commercial female must calve unassisted by their 2nd birthday and breed back annually within 90 days post calving. By holding the herd to this criteria, I indirectly cull the herd of hard doers. Regardless whether the culprit is frame size, mature weight, metabolism/genetics, too much milk, poor feet, what have you-- it doesn't matter--If for any reason body condition compromises fertility to the point they don't breed back within 90 days under the available resources, they are purged from the herd. No need to select for frame, milk, or body type--directly selecting for fertility will address all of that
[*]WEANING WEIGHT %: A commercial female must wean 45-50% of her body weight. Placing direct selection pressure on weaning weight % indirectly addresses much of the redundancy in the selection protocols shown by others. A cow that loses a calf because of dystocia will obviously fail to meet the required weaning weight % and thus will be culled. *A dead calf may be an economic loss but it is never a genetic loss.* If a cows udder is too poor to be functional or if the cow's milk production is insufficient, the calf will either die soon after birth or it's growth rate will be so low that it's dam won't meet the necessary 45-50% requirement mandated to stay in the herd. The WW% standard will be devastating to cows much over 1400lbs as seldom to never are cows over this threshold able to wean half their weight without supplementation. The 45-50% should be done on summer pasture without any type of creep feed. I'm looking to see how much weight the cow can wean on her own accord- how much the creep feeder can add is irrelevant. In order to accurately assess a true weaning weight %, calves should be born after ending any winter supplementation (as green grass emerges) and weaned before any late fall/winter supplementation begins.
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Once a herd is established where every single female has an unassisted calf every single year-- and every single cow weans a minimum of 45-50% of her body weight, THEN it may be practical to further refine the selection protocol but for most producers, employing the above two criteria alone would have a drastic impact on the profitability/efficiency of their herd.