EPD REFERENCE
Calving ease direct (CED)
, is expressed as a difference in percentage of unassist-
ed 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.
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.
All-Purpose Index (API):
Evaluates sires for use on the entire cow herd (bred to
both Angus first-calf heifers and mature cows) with the portion of their daughters
required to maintain herd size retained and the remaining heifers and steers put
on feed and sold grade and yield.
Terminal Index (TI):
Evaluates sire for use on mature Angus cows with all offspring
put on feed and sold grade and yield.
$Values
are multi-trait selection indexes expressed in dollars per head, to assist
commercial beef producers by adding simplicity to genetic selection decisions. A
$Value has meaning only when used in comparison to the $Value of another animal.
For example, just as with EPDs, variation in $Values between animals indicates
average expected differences in the relative value of progeny if random mating is
assumed and the calves are exposed to the same environment.
Weaned Calf Value ($W):
an index expressed in dollars per head, is the expected
average difference in future progeny performancefor preweaning merit. $W includes
both revenue and cost adjustments associated with differences in birth weight,
weaning direct growth, maternal milk, and mature cow size.
Beef Value ($B):
an index expressed in dollars per head, is the expected average
difference in future progeny performance for postweaning and carcass value
compared to progeny of other sires. The $B value combines the contributions of $F
and $G.
