Influence of dietary lysine level, pre-slaughter fasting, and rendement napole genotype on fresh pork quality

Sixty-four gilts from a commercial hybrid line were selected based on rendement napole (RN) genotype and live weight to evaluate the effects of feeding a lysine-deficient diet and feed withdrawal prior to slaughter on fresh pork quality. Glycolytic potential was measured and the bimodal distribution was utilized to predict RN genotype. Diets containing 4.8 (deficient) or 6.4 g/kg lysine were fed for the last six weeks prior to slaughter. Feed withdrawal treatments were imposed 12 or 36 h prior to slaughter. The lysine-deficient diet increased intramuscular fat content; however, feed withdrawal did not consistently impact fresh pork quality. Pork from RN carriers had a lower ultimate pH and Hunter L*. Results from this study suggest that feeding a lysine-deficient diet can increase the intramuscular fat content of both RN genotypes, but feed withdrawal did not impact pork quality. (C) 2003 Published by Elsevier Ltd.