Selection Tools Definitions
Ribeye Area EPD (RE) , expressed in square inches, is a predictor of the difference in ribeye area of a sire’s progeny compared to progeny of other sires. Fat Thickness EPD (Fat) , expressed in inches, is a predictor of the differences in external fat thickness at the 12th rib (as measured between the 12th and 13th ribs) of a sire’s progeny compared to progeny of other sires. $VALUE INDEXES $Value indexes are multi-trait selection indexes to assist beef producers by adding simplicity to genetic selection decisions. $Values are reported in dollars per head, where a higher value is more favorable. The $Value is an estimate of how future progeny of each sire are expected to perform, on average, compared to progeny of other sires in the database if the sires were randomly mated to cows and if calves were exposed to the same environment. Maternal Weaned Calf Value ($M) , 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, docility, mature cow weight, claw set and foot angle. Weaned Calf Value ($W) , an index value expressed in dollars per head, is the expected average difference in future progeny performance for pre-weaning merit. $W includes both revenue and cost adjustments associated with differences in birth weight, weaning direct growth, maternal milk, and mature cow size. Feedlot Value ($F) , an index value expressed in dollars per head, is the expected average difference in future progeny performance for post-weaning merit compared to progeny of other sires. Grid Value ($G) , an index value expressed in dollars per head, is the expected average difference in future progeny performance for carcass grid merit compared to progeny of other sires. Beef Value ($B) , an index value expressed in dollars per head, is the expected average difference in future progeny performance for post-weaning and carcass value compared to progeny of other sires. Combined Value ($C) , expressed in dollars per head, is an index which includes all traits that make up both Maternal Weaned Calf Value ($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 eventually sell them on a quality-based carcass merit grid. EPDs directly influencing a combined index are: CED, CEM, WW, YW, Milk, HP, DOC, MW, Angle, Claw, DMI, Marb, CW, RE and Fat. ANGUS-ON-DAIRY $VALUE INDEXES Angus-On-Dairy $Value Indexes are bioeconomic selection indexes that allow multiple change in several different traits at once pertaining to a dairy-beef crossbreeding objective. These values are terminal crossbreeding indexes to estimate of how future beef- on-dairy progeny of each Angus sire are expected to perform, on average, compared to beef-on-dairy progeny of other Angus sires if the sires were randomly mated and beef-on-dairy calves were exposed to the same environment.
These indexes were designed as specific crossbreeding tools for Angus bulls being mated to dairy cows. Two indexes have been developed for the dairy market: Angus-On-Holstein ($AxH) , a terminal index, expressed in dollars per head, to predict profitability differences in progeny due to genetic traits weighted by appropriated economics of each Angus sire when mated to Holstein females. The underlying breeding objective assumes Angus bulls will be mated to Holstein females to produce Angus-dairy crossbred calves to be fed and marketed on a quality-based grid. Traits included are as follows: calving ease, growth from birth through the feeding phase, feed intake, dressing percent, yield grade, quality grade, muscling, and height. Angus-On-Jersey ($AxJ) , a terminal index, expressed in dollars per head, to predict profitability differences in progeny due to genetic traits weight by appropriated economics of each Angus sire when mated to Holstein females. The underlying breeding objective assumes Angus bulls will be mated to Jersey females to produce Angus-dairy crossbred calves to be fed and marketed on a quality- based grid. Traits included are as follows: calving ease, growth from birth through the feeding phase, feed intake, dressing percent, yield grade, quality grade, and muscling. MEASUREMENTS Adj. Yrlg. Hip Ht. : Each animal’s hip height measured in inches and adjusted to one year of age. Adj. Yrlg. Scrotal Circumference : The bull’s scrotal circumference measured in centimeters adjusted to one year of age. Adj. %IMF : The percent intramuscular fat (marbling) adjusted to 365 days of age. Heritability for marbling is in the moderate range. %IMF Ratio : The percent above or below average (100 = average) a bull or female is for its marbling scan within its contemporary group. Adj. Yrlg. Ribeye Area : Each animal’s ribeye area measured in square inches and adjusted to one year of age. REA Ratio : The percent above or below average (100 = average) a bull or female is for its adjusted ribeye area. Adj. Rib Fat : This is the off-test backfat measured in inches adjusted to 365 days of age. Rib Fat Ratio : The percent above or below average (100 = average) a bull or female is for its backfat scan within its contemporary group. Adj. Rump Fat : This is the off-test rump fat measured in inches adjusted to 365 days of age. Rump Fat Ratio : The percent above or below average (100= average) a bull or female is for its rump fat scan within its contemporary group. WEIGHTS BW (Birth Weight) : The actual weight in pounds at birth. BWR (Birth Weight Ratio) : The percent above or below average (100 = average) a bull or female is for its actual birth weight. A dj. WW (Adj. Weaning Weight) : The weight in pounds at weaning adjusted to 205 days of age. WWR (Weaning Weight Ratio) : The percent above or below average (100 = average) a bull or female is for its adjusted weaning weight. Adj. YW (Adj. Yearling Weight) : The weight in pounds adjusted to 365 days of age. YWR (Yearling Weight Ratio) : The percent above or below average (100 = average) a bull or female is for its adjusted yearling weight.
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October 18, 2025 • Noon • Coushatta, LA
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