Genetic correlations between test station and on-farm performance traits in Large White and French Landrace pig breeds

Abstract

Abstract Genetic correlations between test station and on-farm performance traits were estimated in Large White (LW) and French Landrace (LF) pig breeds using a restricted maximum likelihood procedure applied to a bivariate individual animal model. Traits recorded in test stations were average daily gain (ADG1), average backfat thickness (BT90), feed conversion ratio (FCR) measured on candidates to selection, average daily gain (ADG2), dressing percentage (DP), estimated carcass lean content (ECLC) and meat quality index (MQI) measured on slaughtered sibs. On-farm traits were age (A100) and average backfat thickness (BT100) at 100 kg. Test station data involved records on 7068 and 3392 candidates, 3332 and 1735 slaughtered sibs for LW and LF breeds, respectively. On-farm data consisted of records from 16670 (LW) and 8244 (LF) pigs of both sexes. Genetic correlations between A100 and ADG1 or ADG2 varied between −0.50 ± 0.05 and −0.67 ± 0.03. BT100 was strongly related to BT90 (0.91 ± 0.03 and 0.91 ± 0.05 in LW and LF breeds, respectively) and ECLC (−0.84 ± 0.05 and −0.70 ± 0.07 in LW and LF breeds, respectively). Strongly favourable genetic correlations were also obtained between FCR and A100 (0.32 ± 0.04 in LW; 0.54 ± 0.06 LF) or BT100 (0.45 ± 0.04 and 0.51 ± 0.06 in LW and LF breeds, respectively). MQI was almost independant of A100, but unfavourably related to BT100 in both breeds. These results tend to indicate that genotype × environment interactions in French national breeding programmes are limited for backfat depth, but remain significant for growth rate.