The Effects of Conjugated Linoleic Acid (CLA) and Feed Intake on Lean Pig Growth and Carcass Composition

Purdue University 1999 Swine Research Report. The challenge to the pork industry is to produce lean pigs without compromising pork quality. The leanest genotypes of pigs have poorer muscle quality (lower color scores, lower percent intramuscular fat, greater drip loss) and poorer fat quality (soft, unsliceable bellies) in comparison to genotypes with average leanness. Conjugated linoleic acid (CLA) refers to a group of linoleic acid isomers that have several biological effects. Scientists at the 1st Annual CLA Forum reported that pigs fed CLA had less backfat, less carcass fat, more carcass lean, improved feed conversion and firmer carcasses. Feeding CLA resulted in decreased feed intake while growth rate was unchanged, thus improving feed efficiency. The studies thereafter (Table 1) have consistently shown that CLA decreases backfat and increases fat firmness, but have been inconclusive in determining the effects of CLA on growth traits. This trial was designed to differentiate between the effects of CLA and the effects of lower feed intake on pig growth and carcass composition of a lean genotype of pigs.