Expected Progeny Difference (EPD), is the prediction of how future progeny of each animal are expected to perform relative to the progeny of other animals listed in the database. EPDs are expressed in units of measure for the trait, plus or minus. Interim EPDs may appear on young animals when their performance has yet to be incorporated into the American Angus Association National Cattle Evaluation (NCE) procedures. This EPD will be preceded by an “I”, and may or may not include the animal’s own performance record for a particular trait, depending on its availability, appropriate contemporary grouping, or data edits needed for NCE. AMERICAN ANGUS ASSOCIATION SELECTION TOOLS
PRODUCTION EPDS Calving Ease Direct (CED), is expressed as a difference in percentage of unassisted births, with a higher value indicating greater calving ease in first-calf heifers. It predicts the average difference in ease with which a sire’s calves will be born when he is bred to first-calf heifers. Birth Weight EPD (BW), expressed in pounds, is a predictor of a sire’s ability to transmit birth weight to his progeny compared to that of other sires. Weaning Weight EPD (WW), expressed in pounds, is a predictor of a sire’s ability to transmit weaning growth to his progeny compared to that of other sires. Yearling Weight EPD (YW), expressed in pounds, is a predictor of a sire’s ability to transmit yearling growth to his progeny compared to that of other sires. Yearling Height EPD (YH), is a predictor of a sire’s ability to transmit yearling height, expressed in inches, compared to that of other sires. Scrotal Circumference EPD (SC), expressed in centimeters, is a predictor of the difference in transmitting ability for scrotal size compared to that of other sires. MATERNAL EPDS Heifer Pregnancy (HP), is a selection tool to increase the probability or chance of a sire’s daughters becoming pregnant as first-calf heifers during a normal breeding season. A higher EPD is the more favorable direction and the EPD is reported in percentage units. Calving Ease Maternal (CEM), is expressed as a difference in percentage of unassisted births with a higher value indicating greater calving ease in first-calf daughters. It predicts the average ease with which a sire’s daughters will calve as first-calf heifers when compared to daughters of other sires. Maternal Milk EPD (Milk), is a predictor of a sire’s genetic merit for milk and mothering ability as expressed in his daughters compared to daughters of other sires. In other words, it is that part of a calf’s weaning weight attributed to milk and mothering ability. Mature Weight EPD (MW), expressed in pounds, is a predictor of the difference in mature weight of daughters of a sire compared to the daughters of other sires. Mature Height EPD (MH), expressed in inches, is a predictor of the difference in mature height of a sire’s daughters compared to daughters of other sires. MANAGEMENT EPDS Docility (Doc), is expressed as a difference in yearling cattle temperament, with a higher value indicating more
favorable docility. It predicts the average difference of progeny from a sire in comparison with another sire’s calves. In herds where temperament problems are not an issue, this expected difference would not be realized. Claw Set EPD (Claw), is expressed in units of claw-set score, with a lower EPD being more favorable indicating a sire will produce progeny with more ideal claw set. The ideal claw set is toes that are symmetrical, even and appropriately spaced. Foot Angle EPD (Angle), is expressed in units of foot-angle score, with a lower EPD being more favorable indicating a sire will produce progeny with more ideal foot angle. The ideal is a 45-degree angle at the pastern joint with appropriate toe length and heel depth. Pulmonary arterial pressure EPD (PAP), is expressed in millimeters of Mercury (mmHg), with a lower EPD being more favorable indicating a sire should produce progeny with a lower PAP score. PAP score is an indicator of susceptibility to high altitude disease commonly experienced at elevations greater than 5,500 feet. Selection for this trait aims to improve the genetic potential for a sire’s progeny to have lower PAP scores thus a lower chance of contracting high altitude disease increasing the environmental adaptability of cattle living in mountain areas. Hair Shed EPD (HS), is expressed in units of hair shed score, with a lower EPD being more favorable indicating a sire should produce progeny who shed their winter coat earlier in the spring. Selection for this trait should improve the genetic potential for a sire’s progeny to shed off earlier increasing the environmental adaptability of cattle living in heat stressed areas and producers grazing endophyte- Carcass Weight EPD (CW), expressed in pounds is a predictor of the differences in hot carcass weight of a sire’s progeny compared to progeny of other sires. Marbling EPD (Marb), expressed as a fraction of the difference in USDA marbling score of a sire’s progeny compared to progeny of other sires. 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 infected (hot) fescue. CARCASS EPDS sire’s progeny compared to progeny of other sires. Group/progeny (C Grp/ Pg and U Grp/Pg), reflects the number of contemporary groups and the
number of carcass and ultrasound progeny included in the analysis. from birth through the feeding phase, feed intake, dressing percent, yield grade, quality grade, and muscling. $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, docility, mature cow weight, claw set and foot angle. Feedlot Value ($F), an index, expressed in dollars per head, to predict profitability differences in progeny due to genetics for postweaning feedlot merit compared to the progeny of other sires. The underlying objective assumes producers will retain ownership of cattle through the feedlot phase and sell fed cattle on a carcass weight basis, but with no consideration of premiums or discounts for quality and yield grade. Traits contributing directly to the index are as follows: yearling weight (gain), carcass weight and dry- matter intake. Combined Value ($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 (EPDs) directly influencing a combined index: calving ease direct (CED) and maternal (CEM), weaning weight (WW), yearling weight (YW), maternal milk (Milk), heifer pregnancy (HP), docility (DOC), mature cow weight (MW), foot angle (Angle), claw set (Claw), dry matter intake (DMI), marbling (Marb), carcass weight (CW), ribeye area (RE) and fat thickness (Fat).
SYMBOLS FOUND IN PEDIGREES # - Animal has achieved Pathfinder status + - Embryo transfer calf
Targeting the Brand (CAB) DNA Tested
ACT BW Actual Birth Weight
CED - Calving Ease Direct EPD
BW - Birth Weight EPD
WW - Weaning Weight EPD
YW - Yearling Weight EPD
YH - Yearling Height EPD
SC - Scrotal EPD
ACT. BW WWR YWR
205-Day Ratio 365-Day Ratio
MILK - Milk EPD MILK - Weight EPD MILK - Height EPD
CED
BW
WW
YW
YH
SC
DOC - Docility EPD
DOC
HP
CEM
MILK
MW
MH
HP - Heifer Pregnancy
CW MARB
RE
FAT
$M
$F
$C
CEM - Calving Ease Maternal EPD
Carcass Weight EPD
$Maternal Weaned Calf Value
Ribeye Area EPD
Fat Thickness EPD
$Combined Value
Marbling EPD
$Feedlot Value
3
Made with FlippingBook - Share PDF online