Growth changes in the distribution of dissectable and intramuscular fat in pigs

Abstract

The subcutaneous, intermuscular and cavity fat depots of the half carcasses of 15 Large White × Landrace castrated male pigs, forming a growth series from 8 to 62 kg live weight, were dissected. Seventy individual muscles of these pigs were analysed for intramuscular fat content. The growth rates of each of the four fat depots, relative to total fat, were similar. Subcutaneous fat was the predominant fat depot over the growth range studied. Both intramuscular fat and non-fat dry matter grew faster than the entire muscles containing them. Growth gradients for the intramuscular fat of muscle groups, relative to either total intramuscular fat or to total fat, were similar to those for the entire muscles. The growth gradients for muscle groups were affected by neither the growth of the contained intramuscular fat nor the contained non-fat dry matter. Intramuscular fat density, but not non-fat dry-matter density, varied throughout the carcass. The fat content of muscles was highest in those that could be useful as subcutaneous insulators.