Page 10 - Monymusk Herefords Catalogue eBook.pdf

BEEF HEIFER INDEX - Estimates the genetic differences between ACCURACY
animals in net profitability per yearling heifer joined for a typical self-
replacing commercial herd where Hereford bulls are joined to either Accuracy (%) is based on the amount of performance information
Hereford or other British breed heifers. Selected heifers are retained available on the animal and its close relatives - particularly
for breeding and so maternal traits are of importance. Steers target the number of progeny analysed. Accuracy is also based on the
510 kg live weight (280 kg HSCW and 7 mm P8 fat depth) and heifers heritability of the trait and the genetic correlations with other
450 kg ( 250 kg HSCW and 8 mm P8 fat depth) at 20 months of age. recorded traits. Hence accuracy indicates the “confidence level” of
the EBV. The higher the accuracy value the lower the likelihood of
change in the animal’s EBV as more information is analysed for that
DAIRY BEEF INDEX - Estimates the genetic differences between animal or its relatives. Even though an EBV with a low accuracy may
animals in net profitability per mixed age dairy cow joined with all change in the future, it is still the best estimate of an animal’s genetic
progeny destined for slaughter. Steers and heifer progeny target merit for that trait. As more information becomes available, an EBV
550 kg live weight (300 kg carcase weight and 6 mm fat depth) at 24 is just as likely to increase in value, as it is to decrease.
months of age and at 475 kg live weight (260 kg carcase weight and 7
mm fat depth) at 22 months, respectively. ACCURACY RANGE INTERPRETATION
EBV should be considered as a preliminary estimate. It
less than 50% could change substantially as more performance information
2021 HEREFORD becomes available.
BREEDPLAN AVERAGES Medium accuracy, usually based on the animal’s own records
and pedigree. Still subject to substantial changes with more
50-74%
information, particularly when the performance of progeny
are analysed.
DIR GL BW 200 400 600 MCW MILK SS
Medium - high accuracy and includes some progeny
+2.1 -0.6 +4.1 +33 +55 +78 +67 +17 +2.0 75-90% information. Becoming a more reliable indicator of the
animal’s value as a parent.
EMA RIB RUMP RBY IMF HP B/H D/B
High accuracy estimate of the animal’s true breeding value. It
+3.5 +0.7 +0.8 +0.8 +0.5 +$110 +$112 +$105 more than 90% is unlikely that the EBV will change much with the addition
of more progeny data.
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