Levels of Aggressiveness in Normal and Amino Acid-Deficient Albino Rats

Abstract

From a randomized block design, each member of a sample of albino rats was paired with every other rat and rated for aggressiveness. From these ratings, four matched groups were formed and testing repeated. Group I was fed an amino-acid-deficient diet; Group II received Purina Chow limited in amt. to the intake of Group I; Group III, Purina Chow in amt. necessary to produce weight changes similar to those of Group I; Group IV unlimited amts. of Purina Chow. Group I had significantly lower hemoglobin levels and total serum protein levels than the other groups. Groups I and III had significantly shorter clotting times. No reliable differences in aggressiveness were found to obtain among the groups. This suggests that aggression is a constitutionally-based trait largely independent of state of nutritional insufficiency.