Page 13 - Sudeley Angus 2021 ebook

Intramuscular Fat EBV (%) is an estimate of the genetic difference in the percentage of
intramuscular fat at the 12/13th rib site in a 400 kg carcase. Depending on market targets, larger
more positive values are generally more favourable.
Docility EBV (%) is an estimate of the genetic differences between animals in temperament.
Docility EBVs are expressed as differences in the percentage of progeny that will be scored with
acceptable temperament (ie. either “docile” or “restless”).

ACCURACY
Accuracy (%) is based on the amount of performance information available on the animal and
its close relatives - particularly the number of progeny analysed. 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 EBV. The higher the accuracy value the lower the likelihood
of change in the animal’s EBV as more information is analysed for that animal or its relatives. Even
though an EBV with a low accuracy may change in the future, it is still the best estimate of an
animal’s genetic merit for that trait. As more information becomes available, an EBV is just as likely
to increase in value, as it is to decrease.
Accuracy values range from 0-99%. The following guide is given for interpreting accuracy:

Accuracy range Interpretation
EBV should be considered as a preliminary estimate. It could change substantially
Less than 50%
as more performance information becomes available.
Medium accuracy, usually based on the animal’s own records and pedigree. Still
50-74% subject to substantial changes with more information, particularly when the perfor-
mance of progeny are analysed.
Medium - high accuracy and includes some progeny information. Becoming a more
75-90%
reliable indicator of the animal’s value as a parent.
High accuracy estimate of the animal’s true breeding value. It is unlikely that the
More than 90%
EBV will change much with the addition of more progeny data.

As a rule, animals should be compared on EBVs regardless of accuracy. However, where two animals
have similar EBVs the one with higher accuracy could be the safer choice, assuming other factors are
equal. For further information please contact NZ Angus or TACE.

TRANSTASMAN ANGUS CATTLE EVALUATION
2021 AVERAGES FOR 2019 BORN CALVES

2021 TACE EBVS FOR 2019 BORN CALVES

Dir Dtrs GL BW 200 400 600 MaTW MILK
+1.8 +2.1 -4.4 +4.2 +46 +84 +110 +95 +16

SS DC CWt EMA RIB RUMP RBY IMF
+1.9 -4.2 +61 +5.4 +0.1 -0.2 +0.4 +1.8

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