The response of early-weaned piglets to various levels of lysine in diets of moderate energy content

Thirty entire male piglets weaned at 21 days of age were used to study the effects of two levels of dietary protein (178 and 194g/kg), each in combination with five levels of supplemental lysine (0, 1·5, 3·0, 4·5 and 6·0g/kg), in diets given ad libitum and containing 14 MJ digestible energy per kg, on performance from 6 to 20 kg live weight. Raising total lysine from 7·2 to 8·7 g/kg diet with 178 g crude protein per kg promoted significant increases in average daily gain, efficiency of food conversion and voluntary food intake, and raised all these parameters to levels exhibited by piglets receiving the basal diet containing 194 g crude protein per kg (8·7 g total lysine per kg). Lysine supplementation of the diet containing 194g crude protein per kg had no effect on growth performance or food intake. Carcass characteristics at 20 kg live weight were not significantly affected by either dietary crude protein or total lysine (P> 005).