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$Value indexes $Value indexes, an economic selection index allows multiple change in several different traits at once pertaining to a specific breeding objective. The $Value is an estimate of how future progeny of each sire are expected to perform, on average, compared to progeny of other sires if the sires were randomly mated to cows and if calves were exposed to the same environment. • Maternal Weaned Calf Value ($M) , an index, expressed in dollars per head, predicts profitability differences from conception to weaning with the underlying breeding objective assuming that individuals retain their own replacement females within herd and sell the rest of the cull female and all male progeny as feeder calves. The model assumes commercial producers will replace 25% of their breeding females in the first generation and 20% of their breeding females in each subsequent generation. Traits included are as follows: calving ease direct, calving ease maternal, weaning weight, milk, heifer pregnancy, teat size, udder suspension, functional longevity, docility, mature cow weight, claw set and foot angle. • Weaned Calf Value ($W) , an index, expressed in dollars per head, to predict profitability differences in progeny due to genetics from birth to weaning. The underlying objective being producers will retain 20% of the female progeny as replacements and sell the rest of the cull females and their male counterparts as feeder calves. Traits included are as follows (in no particular order): birth weight, weaning weight, milk, and mature cow weight. • Feedlot Value ($F) , an index, expressed in dollars per head, to predict profitability differences in progeny due to genetics for postweaning feedlot merit compared to the progeny of other sires. The underlying objective assumes producers will retain ownership of cattle through the feedlot phase and sell fed cattle on a carcass weight basis, but with no consideration of premiums or discounts for quality and yield grade. Traits contributing directly to the index are as follows: yearling weight (gain), carcass weight and dry-matter intake. • Grid Value ($G) , an index, expressed in dollars per carcass, to predict profitability differences in progeny due to genetics for carcass grid merit compared to progeny of other sires. The underlying objective assumes producers will market cattle on an above-industry-average carcass grid. Traits included in the index are as follows (in no particular order): carcass weight, marbling, ribeye area, and fat. • Beef Value ($B) , a terminal index, expressed in dollars per carcass, to predict profitability differences in progeny due to genetics for postweaning and carcass traits. This terminal index assumes commercial producers wean all male and female progeny, retain ownership of these animals through the feedlot phase and market these animals on a carcass grid. Traits included in the index are as follows: yearling weight, dry-matter intake, marbling, carcass weight, ribeye area and fat. • Combined Value ($C) , an index, expressed in dollars per head, which includes all traits that make up both Maternal Weaned Calf Value ($M) and Beef Value ($B) with the objective that commercial producers will replace 20% of their breeding females per year with replacement heifers retained within their own herd. The remaining cull heifer and steer progeny are then assumed to be sent to the feedlot where the producers retain ownership of those cattle and sell them on a quality-based carcass merit grid. Expected progeny differences directly influencing a combined index: calving ease direct, calving ease maternal, weaning weight, yearling weight, maternal milk, heifer pregnancy, teat size, udder suspension, functional longevity, docility, mature cow weight, foot angle, claw set, dry matter intake, marbling, carcass weight, ribeye area, and at thickness.
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