Effect of amino acid imbalance on rats maintained in a cold environment

Abstract

The effect of an aminoacid imbalance createdby adding a mixture of indispensable amino acids devoid of histidine to diets containing 2.5-5.0% of casein has been studied in rats maintainedat 7 or 23.5C. Imbalances createdby including in the diets a quantity of the amino acid mixture equal to the quantity of casein they contained depressed growth and food intake of rats maintained at 23.5C, but were without effect on those maintainedat 7C. Food intake and growth of rats maintainedat 7 C were depressed whenthe amount of unbalanced amino acid mixture included in the diet was 2 or 3 times the amount of casein. Rats maintained at 7 C and offered a choice between an Unbalanced diet and a protein-free diet showed a decided preference for the protein-free diet.