Mn. Fouilloux et al., Genetic correlation estimations between artificial insemination sire performances and their progeny beef traits both measured in test stations, GEN SEL EVO, 32(5), 2000, pp. 483-499
In France, beef traits of artificial insemination (AI) beef bulls are impro
ved through the sequential selection for their own performances and for the
ir male progeny performances, both being recorded in test stations. The eff
iciency of such programmes mainly depends on the genetic correlations betwe
en sire performances and progeny beef traits. Such correlations were indepe
ndently estimated, using the multivariate REML (restricted maximum likeliho
od) method in a Limousin and a Charolais programme. In both breeds, high ge
netic correlations were observed between sires and progeny analogous morpho
logy scores (from 0.64 to 0.82). Genetic correlations estimated between sir
es and progeny growth (from 0.41 to 0.70) were lower probably due to the di
fference of diet in central and progeny stations. Correlations between sire
muscling scores and progeny skeletal frames (and vice-versa) were negative
(from -0.05 to -0.58). The genetic correlations of sire traits with progen
y dressing percentage (DPp) and carcass fatness score (CFp) were only low t
o moderate. These results show that the selection of bulls at the end of pe
rformance testing in test stations may be efficient in improving progeny gr
owth and morphology. However, such a selection is insufficient in improving
their dressing percentage and carcass composition.