Effect of Lysine Levels in Pig Starter Diets on Performance to 20 Kg and on Subsequent Performance and Carcass Characteristics

Experiments were conducted to estimate the lysine requirement of pigs weighing 8 to 20 kg and to determine the effect of dietary lysine level during this early growth period on subsequent performance and carcass characteristics. Lysine levels in corn-soybean meal based diets ranged from .75 to 1.05% (Exp. 1) and .80 to 1.10% (Exp. 2) in .10% increments and from .80 to 1.25% (Exp. 3) in .15% increments. Diets fed to all pigs from 20 kg to termination contained National Research Council-recommended levels of lysine. The addition of lysine significantly improved feed efficiency in all experiments and weight gain in Exp. 1 and 2 during the 8- to 20-kg period. Performance during the periods following 20 kg was similar and not affected by dietary lysine levels fed from 8 to 20 kg. Carcass characteristics were unaffected by starter lysine level. The data indicate that pig performance from weaning (8 kg) to market weight was not influenced by starter diets minimally deficient in lysine.