Variabilité inter races des poids des pièces de carcasse et corrélations génétiques avec les critères de qualité de la viande chez le porc

Weights of primal cuts including loin with the skin and fat trimmed (LON), skin-on ham (JAM), belly (POI), shoulder (EPA) and backfat above the loin (BAR) of the right side of each carcass were recorded in French central test stations from 1999 to 2008. Data were collected on 10 759 Large White dam line (LWF), 6 293 Landrace Français (LF), 2 429 Large White sire line (LWM) and 2 253 Pietrain (PP) pigs. The Pietrain breed differed considerably from the other breeds, particularly by a lower backfat weight and a heavier ham weight. Heritability estimates (h²) were generally high for loin, ham and backfat weights (ranging from 0.43 to 0.61), except for loin weight in Pietrain (h² = 0.29). Heritability estimates were also lower for belly and shoulder weights (ranging from 0.20 to 0.35). Ham weight was genetically independent from loin weight in the two sire lines in contrast to moderate positive genetic correlations (0.18 and 0.37) in the two dam lines. The Pietrain differed from the three other breeds in regard to the genetic correlations between ham and shoulder weights (-0.42 versus 0.01 to 0.11) and between shoulder and backfat weights (0.24 versus -0.42 to -0.36). The majority of genetic correlations between meat quality traits and primal cut weights were not significant. However, selection for heavier weights of lean primal cuts would reduce ultimate pH in the Large White dam line and would lead to paler pork in the three white breeds.