Genetic parameters and trends of meat quality, carcass composition and performance traits in two selected lines of large white pigs

Meat quality, carcass composition and performance traits were measured in t wo selection lines selected for either low backfat thickness (BF) at a fixe d live weight or high live weight (WEIGHT) at a fixed age. The performance traits were measured on 3966 to 3985, carcass composition trait on 278 and meat quality traits on 426 to 490 pigs. The meat quality traits were: pH, m easured 45 min and 24 h after slaughter in M. semimembranosus and M. longis simus, tilter paper score and filter paper weight measuring water-holding c apacity, Japanese colour scale and Hunter's colour measurements and a marbl ing score. Phenotypic and genetic correlations with meat quality traits wer e higher for lean percentage (LEAN%) and WEIGHT than for BF. From the genet ic correlations between performance and meat quality traits and the correla ted genetic response of meat quality traits to selection for performance tr aits, it was concluded that deterioration of meat quality over many generat ions occurs. Correlations indicate that BF as an index trait for leanness w ould result in less deterioration of meat quality than when selecting for L EAN%. The genetic trends showed that selection for WEIGHT resulted in more deterioration of meat quality than selection for BF. A pH measurement 45 mi n after slaughter could be a good indicator for improving water-holding cap acity. (C) 1998 Elsevier Science B.V. All rights reserved.