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W
hat
are
EPD
s
?
An Expected Progeny Difference (EPD) is a prediction of how
future progeny of a sire or dam are expected to perform in
various production and carcass traits which are measurable.
EPDs are expressed in actual pounds, square inches, or
centimeters, (depending on the trait), plus or minus what you
can expect in the weights or measurements of progeny sired
by a particular animal as compared with another animal. The
EPDs of the animals listed in this sale book can be compared
to other animals of the same breed.
The EPDs listed are current as of September 11, 2012.
Updated EPDs can be viewed at www.angus.org.
Average EPDs Angus
CED +5, BEPD +1.8, WEPD +46, YEPD +83, Scrotal +.51,
Marb +.39, RE +.28, Fat +.010.
The EPD information was derived from the 2012 Fall
National Sire Evaluation conducted by the American
Angus Association.
Please ask if you need assistance in
understanding how to use the EPDs.
Average EPDs for Sim Hybrids
CE +9.1, BW 1.2, WW 58.3, YW 87, Milk 22.4, MB .25,
RE +.47
Each EPD has an accuracy value (Acc), which measures
the reliability of the EPD. The higher the accuracy, the
greater the reliability of the EPD and the less it would be
expected to change.
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 -
gives an indication of calving-ease.
Birth Weight EPD predicts the birth weight difference one
can expect from any two sires. When bred to genetically
similar groups of cows, a bull with a Birth EPD of +5.0
should sire calves with an average birth weight 2 pounds
heavier than a bull with a Birth Weight EPD of +3.0.
Experience has shown that an Angus bull with a Birth
Weight EPD of +2.5 or less can be used on first calf
heifers with a minimum of calving problems.
If you do not have heifers to breed and just need a bull
for cows that have calved before, most Angus bulls are
acceptable for use on mature cows from a birth weight
standpoint.
Weaning Weight EPD -
is a prediction of a bull’s ability to
transmit weaning growth to his progeny. For example, Bull
A has a Weaning Weight EPD of +40 pounds and Bull B
has a Weaning Weight EPD of +20 pounds. At weaning,
Bull A’s calves will average 20 pounds heavier.
Yearling EPD -
Yearling Weight EPD takes into account both
pre-weaning and post weaning growth. Yearling weight is
the most heritable of all growth traits. You can expect bulls
with high yearling EPDs to produce fast gaining calves. If
Bull A has a Yearling EPD of +80 and Bull B has a Yearling
Weight EPD of +50, Bull A’s calves will average 30 pounds
heavier than Bull B’s at one year of age.
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.
Milk EPD -
Expressed in pounds of weaning weight that
result from the amount of milk produced by daughters of
a particular bull, as compared to the daughters of other
bulls. If Bull A is +20 for Milk and Bull B is +10, bull
A’s daughters’ calves will weigh 10 pounds heavier at
weaning due to her superior milking ability.
CARCASS EPDs
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. The higher the value,
the higher the amount of intramuscular fat (taste fat) in the
ribeye, which positively affects quality grade.
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.
What is an interim? -
Some EPDs for ET calves will be
preceded by an “
I
.” Interim EPDs are calculated on
animals during the time period between the American
Angus Association National Cattle Evaluations (NCE)
that occur twice each year, once in June and again in
December. An interim value is indicated by an “
I
” in
front of the number. While admittedly low in accuracy,
an interim value gives you a snapshot of the animal’s
value as a parent, and, thus, it provides a temporary
selection-decision tool until the next NCE run in which
enough information is available to calculate a true EPD.
ET calves out of commercial recipient dams receive only
a pedigree-estimated interim EPD with a 0.05 accuracy,
since the EPD is just the average of the sire EPD and
the donor dam EPD.
W.D.A. -
Lifetime weight per day of age (pounds per day).
WDA Ratio -
Relative ranking of an animal’s WDA in
comparison to the average of the group, which is 100.