Stayability (Stay),
Predicts the probability of a bull’s daughters remaining productive until at least 6
years of age since that’s how long it takes a female to breakeven given all the expenses of development.
Baldy or British Maternal Index (BMI$)
, As the name implies, this multi-trait selection index attempts to
measure a bull’s potential profitability when complimenting the British cow base (Angus, Red Angus,
Hereford, etc.).
CARCASS
Ribeye Area (REA),
REA EPDs reflect differences in an adjusted 365-day ribeye area measures based on
carcass measurements of harvested cattle. Sires with relatively higher REA EPDs are expected to
produce better muscled & higher percentage yielding slaughter progeny than will sires with lower REA
EPDs.
Marbling (MB),
Predicts differences for carcass marbling score as expressed in marbling score units.
Higher values are positively correlated with higher carcass quality grades.
Certified Hereford Beef Index (CHB$),
A terminal sire index that is built on a production system where
Hereford bulls sire calves for the CHB market.
12
th
Rib Fat Thickness (Fat, BF),
Predicts differences for carcass fat depth over the 12
th
rib, as expressed
in inches. Increases in fat thickness has a detrimental effect on Yield Grade.
$VALUE INDEXES
$Value indexes are multi-trait selection indexes, expressed in dollars per head, to assist beef producers
by adding simplicity to genetic selection decisions. The $Value is an estimate of how future progeny of
each sire are expected to perform, on average, compared to progeny of other sires in the database if the
sires were randomly mated to cows and if calves were exposed to the same environment.
Calving Ease Index (CEZ$),
This index assumes a bull will only be mated to heifers, not cows. The
potential profitability of the sire is measured by the incidence of live calves at birth. Moderate mature
size is also emphasized in the index, but performance is a not a priority.
Weaned Calf Value ($W)
, an index value expressed in dollars per head, is the expected average
difference in future progeny performance for preweaning merit. $W includes both revenue and cost
adjustments associated with differences in birth weight, weaning direct growth, maternal milk, and
mature cow size.
Feedlot Value ($F)
, an index value expressed in dollars per head, is the expected average difference in
future progeny performance for postweaning merit compared to progeny of other sires.
Grid Value ($G)
, an index value expressed in dollars per head, is the expected average difference in
future progeny performance for carcass grid merit compared to progeny of other sires.
Beef Value ($B)
, an index value 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.
All-Purpose Index (API),
Dollars per cow exposed under an all-purpose-sire scenario. 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.
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