Lysine Toxicity in the Chick

Abstract

An excess of dietary L-lysine either as the hydrochloride or free base depressed the growth rate and produced toxicity symptoms in 14- to 21-day-old chicks fed adequate protein diets. The effect of excessive dietary lysine on tissue composition was to decrease the K concentration of muscle, increase the Na and lysine content of muscle and to increase the lysine content of the liver and plasma. No change occurred in the plasma Na or K. A change with age in electrolyte composition of selected tissues of the chick was demonstrated. These observations suggest that the physiological immaturity of the tissue makes the very young chick susceptible to lysine toxicity.