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♦ EPD Terminology
♦ EPD Terminology

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EPD: Expected Progeny Difference - The expected differences in performance of a sire's progeny when compared to the average progeny of all sires evaluated within the breed. Based on actual performance, progeny performance and relatives' performance.

ACC: Accuracy - The reliability placed on the EPD.

CE, CED: Calving Ease Direct - The difference in percentage of unassisted births, with a higher value indicating greater calving ease in first-calf heifers.

BW: Birth Weight - The birth weights of a bull's progeny when compared to the breed average, in pounds.

WW: Weaning Weight - The adjusted weaning weights of a bull's progeny when compared to the breed average, in pounds.

YW: Yearling Weight - The adjusted yearling weights of a bull's progeny when compared to breed average, in pounds.

UDDR: Udder Suspension (Hereford) - Differences in sire EPDs predict the difference expected in the sires' daughters udder characteristics when managed in the same environment. Weak udder suspension results in pendulous udders that make it difficult for a calf to nurse.

TEAT: Teat Size (Hereford) - Differences in sire EPDs predict the difference expected in the sires' daughters udder characteristics when managed in the same environment. Oversized teats are difficult for newborn calves to nurse and the calf may not receive adequate colostrum.

RADG: Residual Average Daily Gain (Angus) - The adjusted amount of post weaning gain in future progeny, in pounds, given a constant amount of feed consumed.

ADG: Average Daily Gain (Simmental) - The difference in pounds of daily gain expected between animals' progeny during the post weaning feeding period.

SCR, SC: Scrotal Circumference (Angus, Charolais, Hereford) - The adjusted yearling scrotal circumferences of a bull's progeny when compared to breed average, in centimeters.

DOC: (Angus) - The difference in yearling cattle temperament, with a higher value indicating more favorable docility.

CETM, CEM, MCE: Calving Ease Total Maternal, Calving Ease Maternal, Maternal Calving Ease - The difference in percentage of unassisted births with a higher value indicating greater calving ease in first-calf daughters.

Milk, MM: Maternal Milk - The amount of pre-weaning performance gained by calves which can be attributed to the milking ability of a bull's daughters, expressed in pounds of calf.

TM, MWW: Total Maternal, Maternal Weaning Weight (Red Angus, Simmental, Charolais) - Measure of as ire's ability to transmit milk production and growth rate through his daughters. Predicts the weaning weight of a sire's daughters' calves. Equal to his milk EPD plus half his WW EPD.

M&G: Maternal Milk & Growth (Hereford) - The Milk EPD plus half the WW EPD. A sire's M&G EPD reflects what he is expected to transmit to his daughters for a combination of growth genetics and maternal production.

ME: Maintenance Energy (Red Angus) - Differences in mature cow maintenance energy requirements. Expressed as megacalories per month.

HPG, HP: Heifer Pregnancy (Red Angus, Angus) - Differences in percent probability of female progeny conceiving to calve as 2-year-olds; a more accurate measurement than her sire's or paternal brothers' scrotal circumference.

MkH: Milking Herds (Angus) - Indicates the number of herds from which daughters are reported.

MkD: Milking Daughters (Angus) - Reflects the number of daughters having progeny weaning weight records included in the analysis.

MW: Mature Weight (Angus) - A predictor of the difference in mature weight of a sire's daughters compared to the daughters of other sires, expressed in pounds.

MH: Mature Height (Angus) - A predictor of the difference in mature height of a sire's daughters compared to the daughters of other sires, expressed in inches.

STAY: Stayability (Red Angus, Simmental) - Differences in percent probability of daughters staying productive past the age of six.

CW: Carcass Weight (Angus, Simmental, Charolais, Red Angus) - The adjusted carcass weights of a sire's progeny, expressed in pounds.

MB, MARB, IMF: Marbling - A predictor of the difference in a sire's progeny for percent marbling score or percent intramuscular fat in the ribeye muscle compared to other sires.

YG: Yield Grade (Simmental) - Expressed as a deviation of Yield Grade units where negative values are desirable.

REA, RE: Ribeye Area - Adjusted ribeye area of a sire's progeny, measured in square inches.

FAT, BF: Back Fat - The adjusted twelfth rib fat thickness of a sire's progeny, expressed in inches.

SHR: Shear Force (Simmental) - Pounds of force required to shear a steak.

Carc H/P and Ult H/P: Group/progeny (Angus) - Reflects the number of contemporary groups and the number of carcass and ultrasound progeny included in the analysis.

I: Interim - The EPD is based on performance information of a bull's sire, dam and relatives.

P: Pedigree estimate.

$EN: Cow Energy Value (Angus) - Assesses differences in cow energy requirements as an expected dollar savings difference in daughters of sires, expressed in dollar savings/cow/year. A larger value is more favorable when comparing two animals. $EN savings include lactation energy requirements and energy costs associated with differences in mature cow size.

$W: Weaned Calf Value (Angus) - The expected average difference in future progeny performance for pre-weaning merit, expressed in $/head. $W includes both revenue and cost adjustments associated with differences in birth weight, weaning direct growth, maternal milk and mature cow size.

$F: Feedlot Value (Angus) - Calculates a $/head difference in expected progeny performance for post weaning merit. $F uses WW and YW EPDs along with trait inter-relationships. Typical feedlot gain value, feed consumption and cost differences are accounted for in the final calculations.

$G: Grid Value (Angus) - Combines quality grade and yield grade attributes, and is calculated for animals with carcass EPDs, ultrasound EPDs or both types of EPDs. A three-year rolling average is used to establish typical industry economic values for quality grade and yield grade schedules.

$B: Beef Value (Angus) - The expected average dollar per head difference in the progeny post weaning performance and carcass value. The $B value is comprised of two pieces: $F and $G.

API: All-Purpose Index (Simmental) - Evaluates sires for use on the entire cow herd (bred to both Angus first-calf heifers and mature cows) with daughters retained and remaining heifers and steers put on feed and sold grade and yield.

TI: Terminal Index (Simmental) - Evaluates sires for use on mature Angus cows with all offspring put on feed and sold on a grade and yield basis.

BMI$: Baldy Maternal Index (Hereford) - An index to maximize profit for commercial cow/calf producers who use Hereford bulls in rotational crossbreeding programs on Angus-based cows and heifers. Retained ownership of calves is assumed, with fed cattle marketed on a Certified Hereford Beef® (CHB) pricing grid.

CEZ$: Calving EZ Index (Hereford) - Similar to BMI$, except Hereford bulls are mated only to yearling heifers. Increased emphasis on CE and MCE compared with the other index.

BII$: Brahman Influence Index (Hereford) - This index is similar to BMI$, except Hereford bulls are used in rotational crossing with Brahman rather than Angus. Greater emphasis placed on traits deficient in Brahman-cross cattle, (fertility and age at puberty) and less on acceptable traits (growth and calving ease).

CHB$: Certified Hereford Beef Index (Hereford) - A terminal sire index where Hereford bulls are mated to British-cross cows and all offspring are sold as fed cattle on a CHB pricing grid.

HB: HerdBuilder (Red Angus) - Used by producers to increase the sustainability of the cow herd and ultimately their operation. HB assumes bulls will be mated to both cows and heifers, replacement females will be retained within the herd, and the remaining progeny will be sold on a quality based carcass grid.

GM: GridMaster Index (Red Angus) - Used by producers whose primary goal is to maximize profitability of feeders in the feedyard and on the rail. GM assumes bulls will be mated to cows only, and all progeny will be sold on a quality base carcass grid.

TSI: Terminal Sire Index (Charolais) - Combines BW, WW, YW, REA, HCW, MARB and FAT into one single value. The TSI uses estimates of the genetic relationships between traits with an economic default value based on three year rolling USDA data.


January 2016


 
 
 
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