A comparison of ‘on-farm’ and station testing in pigs

Abstract
SUMMARY Data from 14 074 gilts, performance-tested on 66 farms, were matched with those from 3835 station-tested boar sibs, the whole comprising progeny test results on 456 sires. Both groups of data were adjusted independently for effect of month of test and the farm data further adjusted to a constant weight of 91 kg. Analysis of variance and covariance was carried out within herds using weighted sire progeny means. Phenotypic correlations between the same traits recorded ‘on-farm’ and in station, ranged from 0·12* (weight/age) to 0·25** (‘C’ + ‘K’ fat depth) while genetic correlations, computed using the estimated accuracy of each test, ranged from 0·23* (weight/age) to 0·49** (simple performance test index). Correlations were generally higher in Large White than in Landrace pigs.