Genetic relationships between intramuscular fat content and meat quality, carcase, production and reproduction traits in Australian pigs

Intramuscular fat content was recorded on 1011 Large White, 870 Landrace and 186 Duroc pigs. All three breeds had a mean intramuscular fat content below the recommended level of 2.5% to improve eating quality with values of 1.59%, 1.68% and 2.47%, respectively. Heritability estimates were 0.29 for Large White and 0.42 for Landrace. Genetic correlations between intramuscular fat content and average daily gain, feed intake and backfat were -0.21, 0.03 and 0.19, respectively. Selection for higher leanness will therefore reduce intramuscular fat content. Intramuscular fat content was favourably correlated with the meat quality traits pH measured 45 minutes and 24 hours after slaughter (r_g: 0.48 and -0.20) and drip loss percentage (r_g: -0.06). A higher intramuscular fat content was genetically associated with a lighter colour (r_g: 0.26). Considering reproduction traits, only litter birth weight was significantly related to intramuscular fat content (r_g: -0.26 to -0.37).