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Adj. 365-day SC
is the scrotal circumference at the end of the test, in cm., adjusted to 365 days of age.
Adj. REA
and
Adj. Rib Fat
are the Rib Eye Area and Rib Fat measured by ultrasound at the 12th rib,
adjusted to 365 days of age. Breed-specific adjustments are used. ^ Denotes that the breed
association does not adjust this ultrasound information to 365 days of age, so this is the actual record
(unless otherwise specified).
Adj. REA/cwt
is the adjusted Rib Eye Area expressed per hundred
pounds of live weight. The 365-day weight is used as the live weight measurement; if REA is not
adjusted to 365 days, the weight at scanning is used.
Adj. % IM Fat
is the % intramuscular (IM) fat measured by ultrasound, adjusted to 365 days of age.
^ Denotes that the breed association does not adjust % IM fat to 365 days of age, so this is the actual
record (unless otherwise specified). In parentheses is the % IM fat expressed as a ratio, which
compares the % IM fat to the breed average. A ratio of 111 indicates the bull had 11% more % IM
fat than the average of his breed in this test. If there are fewer than 6 bulls of one breed, the ratio is
based on the average % IM fat of all bulls on test. The % IM fat is a measure of marbling, which is
one of the major factors influencing carcass Quality Grade. Comparing within a breed, bulls with
higher % IM fat should sire calves with a greater ability to have a higher carcass Quality Grade than
calves sired by bulls with lower % IM fat.
% Retail Product
is estimated as 65.59 - 9.931*(Rib Fat) + 1.2259*(Rib Eye Area) - 0.013166*(Carcass
Weight) - 1.29*(KPH). Rib Fat and Rib Eye Area are adjusted to 365 days of age. Carcass Weight
was estimated as .60*(365-day Weight); if the breed association does not adjust ultrasound
information to 365 days of age, the weight at scanning is used instead of 365-day weight. A KPH
(kidney, pelvic and heart fat) value of 2.0% was used for all bulls. In parentheses is the % retail
product expressed as a ratio, which compares the % retail product to the breed average. A ratio of
102 indicates the bull is estimated to have 2% more % retail product than the average for his breed in
this test. If there are fewer than 6 bulls of one breed, the ratio is based on the average % retail
product of all bulls on test. The % retail product is heavily influenced by rib fat thickness and rib eye
area, and highly related to carcass Yield Grade. Lower rib fat thickness and larger rib eye area result
in greater % retail product. Comparing within a breed, bulls with higher % retail product values
should sire calves with carcasses having more desirable Yield Grades than bulls with lower % retail
product values.
Carcass Merit
is calculated as (% Retail Product Ratio + % Intramuscular Fat Ratio)/2. In this example,
the carcass merit is (111+102)/2 = 106.3, indicating that his carcass merit is 6.3% above the breed
average. Carcass merit is an attempt to provide an indicator of both carcass Quality Grade and
carcass Yield Grade. Ideally, we would prefer bulls that were above average in both % retail product
and in % IM fat. However, this is not always possible. Producers whose calves tend to have less
than desirable Quality Grades need to place greater emphasis on % IM fat, while those with calves
that tend to have poor Yield Grade (i.e., few Yield Grade 1 and 2 with some Yield Grade 4) need to
place greater emphasis on % retail product.
EPDs:
EPDs and (Accuracies) are given for several traits: Birth Weight, Weaning Weight, Yearling
Weight, Maternal Milk, Direct Calving Ease, Maternal Calving Ease, Docility, Carcass Weight,
Marbling, Rib Eye Area, Fat Thickness, Yield Grade, and Days to Finish. Exact traits will be
different for each breed. “Genomic EPDs” means that the bull himself had a genomic test done, and
this was incorporated into his EPDs. See the article
EPDs and $ Indexes
for more information. The
numbers in asterisks indicate the percentile group ranking of the bull in the breed, in 10% groups:
*10* is in the top 1-10%, *9* is 11-20%, and so on; *2* is 81-90%; and *1* is 91-100% (the bottom
10%). Bulls are compared to non-parent EPDs from their respective breed associations; it is a
ranking within the entire breed, not just the bulls in this test. It is only valid to compare EPDs of
bulls within the same breed. Do not compare EPDs of bulls in different breeds.
