Page 15 - Puke-Nui Angus Catalogue eBook.pdf

HERITABILITIES OF TRAITS IN ANGUS TACE

Only part of the variation that we observe Calving Ease Dir 14% 86%
among animals is due to genetic differences.
The majority of the variation is general due Gestation Length 65% 35%
to non-genetic factors such as differences Birth Wt 32% 68%
in environment and nutrition. The degree 200-Day Wt 12% 88%
to which genetic differences influence
performance varies from trait to trait. This is 400-Day Wt 23% 77%
explained by differences in the ‘heritability’ of 600-Day Wt 35% 65%
the traits.
Growth and carcase traits tend to have Mature Cow Wt 40% 60%
moderate to high heritabilities (i.e 20 to Milk 10% 90%
40%), whilst female fertility and calving ease Scrotal Size 39% 61%
have low heritabilities (10% or lower). TACE
takes into account the different degrees of Days to Calving 7% 93%
heritability of various traits and the known Carcass Wt 41% 59%
genetic relationships between traits.
Eye Muscle Area 34% 66%
Rib Fat 45% 55%
The amount of genetic Rump Fat 32% 68%
influence in a trait. Retail Beef Yield % 60% 40%
The amount of environmental Intra-muscular Fat % 32% 68%
(non-genetic) influence in a trait.
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