The increase in kill-out proportion with increasing
slaughter weight found here has also been observed
previously (Keane, 1994; Keane et al., 2001) but the
magnitude has varied greatly between experiments.
In the present experiment, mean kill-out increased by
13 g/kg for a carcass weight increase of 50 kg.
Corresponding values for a similar carcass weight
increase reported previously have ranged from 4 g/kg
(Keane et al., 2001) to 18 g/kg (Keane, 1994).
The absence of a difference in carcass grades
between NZ and EU was surprising considering that
the strains differed in most measures of fatness and in
ribs composition. In a recent analysis of a large data
set of over 900 carcass side dissections, carcass
conformation class was not significantly related to
either fat or muscle proportions but was negatively
related to bone proportion (Keane et al., 2000). In the
same study, carcass fat class was significantly related
to the proportions of all three carcass tissues but the
proportions of total variance accounted for either by
fat class alone or by conformation and fat class
combined were small.
Differences between the dairy strains in carcass
measurements were small especially when scaled for
carcass weight. Nevertheless, the differences were
generally significant and in all cases the EU values