Lysine supplementation of diets for pigs between 7 and 56 days of age

Abstract

ABSTRACTSixty entire male pigs between 7 and 28 days and 60 entire male pigs between 28 and 56 days of age were given ad libitum basal diets using peanut meal and wheat gluten with or without dried milk as the protein supplements. The diets contained between 7·0 and 10·7 g lysine per kg. These diets were supplemented with graded additions of synthetic L-lysine hydrochloride.It was found that the lysine required for maximum performance and nitrogen retention was at least 12·7 g/kg dry matter (DM) between 7 and 28 days of age and not greater than 12 g/kg DM between 28 and 56 days of age. These values are 4·7 and 5·3 g/kg dietary crude protein for the two ages or 0·81 and 0·79 g/MJ digestible energy.A method is discussed for the calculation of the most economical level of lysine supplementation. This is dependent on the cost of the basal diet and lysine, and the value of the weight gain.The concentration of free lysine in the blood plasma did not give a clear indication of lysine requirement of the pigs.