Socialization, the sequencing of environmental factors, and their effects on weight gain and disease resistance of chickens.

Weight gain following a 60-hr fast was influenced 1) by prior experiences of either a presence or an absence of a similar initial fast followed by either being moved to unfamiliar quarters or being fed corticosterone or 2) whether or not the chickens were socialized. Socialization, but not the environmental stresses, increased antibody response to erythrocyte antigens and increased resistance to Escherichia coli challenge. Although the experimental cockerels had increased heterophil/lymphocyte ratios following the feeding of corticosterone, their antibody response to erythrocyte antigen and their resistance to E. coli challenge were not altered. The presence or absence of water deprivation stress early in life failed to alter any results.