Page 12 - Ranui Catalogue 2021 ebook

UNDERSTANDING The transtasman angus cattle Evaluation (tace)

UNDERSTANDING THE
TRANSTASMAN ANGUS CATTLE
EVALUATION (TACE)

What is the TransTasman Angus Cattle Evaluation? Or similarly, a bull with an IMF EBV of +3.0 would be
The TransTasman Angus Cattle Evaluation is the genetic expected to produce progeny with on average, 1% more
intramuscular fat in a 400 kg carcase than a bull with a IMF
evaluation program adopted by Angus Australia for Angus EBV of +1.0 (i.e. 2% difference between the sire’s EBVs, then
and Angus influenced beef cattle. The TransTasman Angus halved as the sire only contributes half the genetics).
Cattle Evaluation uses Best Linear Unbiased Prediction
(BLUP) technology to produce Estimated Breeding Using EBVs to Benchmark an Animal’s Genetics with the
Values (EBVs) of recorded cattle for a range of important Breed
production traits (e.g. weight, carcase, fertility). EBVs can also be used to benchmark an
The TransTasman Angus Cattle Evaluation is an international animal’s genetics relative to the genetics of other Angus or
genetic evaluation and includes pedigree, performance and Angus infused animals in Australia.
genomic information from the Angus Australia and Angus To benchmark an animal’s genetics relative to other Angus
New Zealand databases, along with selected information animals, an animal’s EBV can be compared to the EBV
from the American and Canadian Angus Associations. reference tables, which provide:
The TransTasman Angus Cattle Evaluation utilises a range • the breed average EBV
of genetic evaluation software, including the internationally • the percentile bands table
recognised BLUPF90 family of programs, and BREEDPLAN®
beef genetic evaluation analytical software, as developed The current breed average EBV is listed on the bottom of
by the Animal Genetics and Breeding Unit (AGBU), a joint each page in this publication, while the current EBV reference
institute of NSW Agriculture and the University of New tables are included at the end of these introductory notes.
England, and Meat and Livestock Australia Limited (MLA). For easy reference, the percentile band in which an animal’s
What is an EBV? EBV ranks is also published in association with the EBV.
An animal’s breeding value can be defined as its genetic Considering Accuracy
merit for each trait. While it is not possible to determine An accuracy value is published with each EBV, and is usually
an animal’s true breeding value, it is possible to estimate displayed as a percentage value immediately below the
it. These estimates of an animal’s true breeding value are EBV.
called EBVs (Estimated Breeding Values). The accuracy value provides an indication of the reliability
EBVs are expressed as the difference between an individual of the EBV in estimating the animal’s genetics (or true
animal’s genetics and a historical genetic level (i.e. group breeding value), and is an indication of the amount of
of animals) within the TACE genetic evaluation, and are information that has been used in the calculation of the
reported in the units in which the measurements are taken. EBV.
Using EBVs to Compare the Genetics of Two Animals EBVs with accuracy values below 50% should be considered
as preliminary or of low accuracy, 50-74% as of medium
TACE EBVs can be used to estimate the expected difference accuracy, 75-90% of medium to high accuracy, and 90%
in the genetics of two animals, with the expected difference or greater as high accuracy.
equating to half the difference in the EBVs of the animals,
all other things being equal (e.g. they are joined to the Description of TACE EBVs
same animal/s). EBVs are calculated for a range of traits within TACE, covering
For example, a bull with a 200 Day Growth EBV of +60 would calving ease, growth, fertility, maternal performance,
be expected to produce progeny that are, on average, 10 carcase merit, feed efficiency and structural soundness.
kg heavier at 200 days of age than a bull with a 200 Day A description of each EBV included in this publication is
Growth EBV of +40 kg (i.e. 20 kg difference between the provided on the following page.
sire’s EBVs, then halved as the sire only contributes half the
genetics).

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