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EPDs - |
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Animal names that you see in the results of a search display the animal's registration number in parentheses at the end of the name. You may also see animals have codes listed in curly brackets {} between the animal name and registration number. These codes represent either awards the animal has received or genetic abnormalities the animals is known to be tested free of or a carrier of. Currently used codes are listed below:
DOD
= Dams of Distinction Award
SOD = Sire of Distinction Award
CHB = CHB Sire Award
HYC = Hypotrichosis Carrier
DLF = Dilutor Free (tested and results indicate animal is not a carrier)
DLC = Dilutor Carrier
IEF = Idiopathic Epilepsy Free (tested and results indicate animal is not a
carrier)
IEC = Idiopathic Epilepsy Carrier
EPD’s are an estimate of an animal's genetic worth for that particular trait. An EPD is expressed in the units of measure for that trait. EPD’s are based on a combination of performance information from an animal's pedigree, individual and progeny performance. EPD’s can be used to predict one animal's progeny performance compared to another's progeny. EPD’s can also be used to compare the genetic worth of one animal to the overall Hereford population average and distribution. Each calculated EPD has an associated accuracy value.
An accuracy value calculated by the genetic analysis is a number between 0 and 1. Accuracy is a relative indicator of the confidence you can place in that particular EPD. The closer an accuracy is to one, the more reliable is the estimate.
Accuracy ranges from 0-99% and indicates the probability of an EPD changing with the addition of more progeny data. The magnitude of possible change decreases as accuracy increases. Accuracy below 75% should be regarded as low, between 76-90% as medium and above 90% as high.
An EPD with an accuracy of "P" is "Pedigree Estimate" and is simply the exact average of that animal's parents. An EPD with an accuracy of "P+" is an "Interim EPD" and is the parental average adjusted by the animal's individual performance compared to his contemporaries.
Accuracy is based on the amount of performance information available on the animal and its close relatives - particularly the number of progeny analyzed. Accuracy is also based on the heritability of the trait and the genetic correlations with other recorded traits. Hence accuracy indicates the "confidence level" of the EPD.
Regn. No: The Association Registration Number of the animal.
Name: The registered name of the animal.
Calving
Ease – Direct (CE) :
CE EPDs are based on calving ease scores and birth weights. More positive EPDs
are favorable and indicate easier calving. The EPD for direct calving ease
indicates the influence of the sire on calving ease in purebred females calving
at two years of age.
Birth
Weight (BW) :
The BW EPD is an indicator of birth weight and calving
ease. Progeny sired by a bull with a BW EPD of 2.2 can be expected to
weigh 3.2 lb. more at birth, on average, than progeny sired by a bull with an
EPD of -1.0 lb. (2.2 minus -1.0 = 3.2 lb.) Birth weight is another indicator of
calving ease. Larger BW EPDs usually, but not always, indicate more calving
difficulty.
Weaning
Weight (WW) :
The WW EPD reflects pre-weaning growth potential. Measured
from adjusted 205-day weight. It is an indicator of direct genes
for growth independent of milk production of the dam. Calves sired by a bull
with a WW EPD of 30 should have a 20 lb. advantage in 205-day adjusted weaning
weight compared to calves sired by a bull with an EPD of +10 lb. (30 minus 10.0
= 20 lb.).
Yearling
Weight (YW) :
YW EPD for a sire with an EPD of 87 indicates that on average, his progeny
should be 30 lb. above the average of progeny of a bull with an EPD of 57 lb.
YW EPD reflects differences in the 365-day adjusted yearling weight for
progeny. It is the best estimate of total growth.
Maternal
Milk (MM) :
The MM EPD is a prediction of weaning weight differences due to milk and
maternal ability of the dam. For a sire, the MM EPD predicts the maternal
ability of his daughters expressed in pounds of calf weaned. MM EPD’s do not
specifically predict pounds of milk produced, but pounds of calf weaned due to
maternal production of the dam. It predicts the difference in average
weaning weight of sires’ daughters’ progeny due to milking ability. Daughters
of a sire with a MM EPD of 14 should produce progeny with 205-day weights
averaging 24 lb. more (as a result of greater milk production) than daughters
of a bull with a MM EPD of -10 lb. (14 minus -10.0 = 24 lb.). This difference
in weaning weight is due to total milk production over the entire lactation
period.
Maternal
Milk & Growth (MG) :
The MG EPD is a combination EPD. It is the MM EPD
plus 1/2 the WW EPD. It has no accuracy value since it is simply a combination
of two other EPD’s. A sire's MG EPD reflects what he is expected to transmit to
his daughters for a combination of both growth genetics (WW EPD) and maternal
production (MM EPD). This EPD is sometimes referred to as “total
maternal” or “combined maternal.”
Maternal
Calving Ease (MCE)
The MCE EPD indicates how easily a sire's daughters will
calve at two years of age. When compared to the daughters of other sires.
Mature
Cow Weight (MCW)
MCW EPDs reflect differences in mature cow size. Mature cow weights are taken at the time
their calves are weaned. Mature cow size
can be an important factor in overall profitability of a cow herd due to the
increased costs associated with maintaining larger cows year round.
Scrotal
Circumference (SC) :
Measured in centimeters and adjusted to 365 days of age, SC EPD is the best
estimate of fertility. It is related to the bull's own semen quantity and
quality, and is also associated with age at puberty of sons and daughters.
Larger SC EPDs suggest younger age at puberty. Yearling sons of a sire with an
EPD of 0.7 should have yearling scrotal circumference measurements that average
0.7 cm. larger than progeny by a bull with an EPD of 0.0. In this genetic
analysis, a multiple-trait model was used for scrotal circumference. Weaning
weight was used as a predictor variable to increase the prediction accuracy of
SC EPDs. Therefore, an animal with a weaning weight EPD should also have an SC
EPD.
Rib
Fat (FAT) :
The FAT EPD reflects differences in adjusted 365-day, twelfth-rib fat thickness
based on ultrasound measurements of live yearling cattle. Sires with low, or
negative, FAT EPDs are expected to produce leaner
progeny than sires with higher EPDs. Ultrasound measures have been shown to be
highly correlated with the performance of slaughter progeny.
Ribeye
Area (REA) :
REA EPDs reflect differences in an adjusted 365-day ribeye
area measures based on ultrasound measurements of live yearling cattle. Sires
with relatively higher REA EPDs are expected to produce better muscled and
higher percentage yielding slaughter progeny than will sires with lower REA
EPDs
Marbling
(MARB) :
MARB EPDs reflect differences in an adjusted 365-day
intramuscular fat (marbling) score based on ultrasound measurements of live
yearling cattle. Breeding cattle with higher MARB EPD’s should produce
slaughter progeny with a higher degree of intramuscular fat and therefore higher
quality grades.
Profit
indexes are not silver bullets! The four indexes which have been formulated by
the AHA are to be used to assist Hereford breeders in using the genetic
evaluations to potentially improve profitability for commercial producers.
These indexes have been designed using multiple traits. These indexes are
formulated on general representations of beef production systems used in the
U.S. and consider a group of economically relevant traits that characterize
those systems. Relative economic values for this group of traits are paired up
with the EPD to produce a $ index value. The difference in the $ value of the
index predicts the difference in profit. Each of the indexes utilizes
crossbreeding to capture the value of heterosis. The
indexes also include cost of production for all phases of production (cow-calf,
feedlot and harvest). The income is derived at the carcass endpoint based on
quality, weight and grade and yield. The economic values are based on past
values with some forecast for what economists believe the future holds. The
economic values assigned to each trait can be changed at any time that it looks
to be necessary.
BMI Index
-The Baldy Maternal Index is a maternally focused index that has a production
system based off of 1000 Hereford x Angus females with a progeny harvest
endpoint directed towards CHB. This index is more critical of CE than the
Brahman Influence Index and also has significant weight on fertility. There is
positive weight on WW and a slightly negative weight on YW which promotes early
growth and then a slow down on growth to keep mature size manageable. The
weight for MARB is greater than the weight for REA. This is true because of the
price difference between the choice-select spread and the fact that there is
very little incentive to produce cattle better than a yield grade 3. The
question comes up concerning the fact that our branded beef program (CHB) has
been successful because of the acceptance of Select cattle. In answer to this,
we are using a crossbreeding production system that could sell cattle on
several grids and that our CHB program is installing a choice product. This
index is geared to service any commercial program that runs British cross cows.
CEZ Index
-The Calving Easy Index is a general purpose index that focuses on identifying
bulls that can be used on heifers and then ultimately the calves will be
marketed through CHB. As you might expect, CE and MCE has significant weight in
this index along with fertility. There is very little weight put on growth
traits and less emphasis on carcass. Remember, this is a general index that is
specifically designed to be used in a heifer program.
BII Index
-The Brahman Influence Index is a maternally focused index that is based off of
a 1000 head cow herd of Brahman x Hereford cross cows. The progeny for this
index will be harvested in a commodity based system since CHB does not allow
Brahman influenced cattle into the program. This index has less emphasis for CE
than any of the other indexes. There is emphasis on both REA and MARB since the
cattle will be harvested through a commodity market. The largest emphasis in
this index is in fertility which is measured solely by Scrotal Circumference at
the present time. Obviously, the target for this index is the producers in the
Southern regions of the US where the bulls are typically sold to commercial
cattlemen that have Brahman Influenced cow herds.
CHB Index
-The CHB Index is a terminal sire index that is built on a production system
where Hereford bulls sire calves for the CHB market. There is some pressure put
on CE and then positive weight on both WW and YW. Remember that all offspring
in this index are harvested, so we want them to be born alive and then grow
fast at all stages of life. Of course, we have a much heavier weight value on
fat in this index, as we want the cattle to stay lean. There is also a
significant weight on both REA and MARB with more emphasis again on MARB. This
index would be used by producers who have a target of producing bulls for a
terminal breeding program. This index could be used heavily in the Midwest
where bulls are used in rotational breeding programs to produce cattle in a
retained ownership program or simply sold to backgrounders. This is the only
index that has no emphasis on fertility. Remember that nothing is retained in
the herd.
When you see the following displayed below the EPD table in your search results:
Statistics: BW: 72/306, WW: 70/287, YW: 33/116, SC: 6/35, Dgt: 32, Fat: 34, REA: 15, MARB: 3
Here is what it means:
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BW: 72/306 - |
"72" is the number of herds in which progeny were raised with recorded birth weight measurements. This includes herd counts from AHA & CHA. Number of herds gives a general indication of progeny distribution for each of the traits. "306"
is the number of progeny out of the animal with recorded measurements for
each specific trait. This includes the progeny counts from AHA &
CHA. Number of progeny should not be used in lieu of accuracy, but
simply to further clarify accuracy values. |
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Dgt: 32 - |
The number of
daughters sired by the bull which have produced progeny with weaning weight
records. This includes the daughter counts from AHA & CHA.
Number of daughters should not be used in lieu of accuracy, but simply to
further clarify Maternal Milk and Maternal Milk & Growth accuracy values. |
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REA: 15 - |
The number of
scan progeny recorded for each of the carcass traits. |
These statistics are calculated at the time of each genetic analysis. Therefore, they will only be updated when new EPD results are reported.