Performance records of 1459 Polled
Hereford cattle born from 1967 through 1979
were analyzed to estimate genetic parameters
and the direct and correlated responses that
were due to selection for feed conversion.
Heritabilities were .24 for intake, .25 for gain,
and .14 for feed conversion. The genetic correlation
between average daily gain and feed
conversion was -.82; correlation between
average daily gain and feed intake was .42.
Faster-gaining cattle have greater feed intakes
and are more efficient. Feed conversion was
improved by direct selection. However, it is
more economically feasible for breeders to
improve feed conversion by selecting for faster
rates of gain, rather than selecting for the trait
directly.