Page 13 - Wairere 2021 Catalogue ebook
P. 13
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
less than 50% change substantially as more
performance information
becomes available.
Medium accuracy, usually based
on the animal's own records and
pedigree. Still subject to
50-74% substantial changes with more
information, particularly when
the performance of progeny are
analysed.
Medium - high accuracy and
includes some progeny
75-90% information. Becoming a more
reliable indicator of the animal's
value as a parent.
High accuracy estimate of the
animal's true breeding value. It
more than 90% is unlikely that the 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.