IMMUNOSUPPRESSION IN BROILERS EXPOSED TO INCREASED TEMPERATURE

Abstract

Effect of prolonged and intermittent exposure to increased atmospheric temperature on the immune responses was studiedexperimentally in 154 broilers. It was observed that 40 ± 1 ° C for 29 days, 12 h. a day depressed both humoral and cell-mediated immunity. There was a reduction in the weight of the lymphoid organs (bursa of Fabricius, spleen and thymus) consequent to depletion of medullary lymphocytes of bursa of Fabricius and a decrease in haemagglutination inhibition titres against N.D. Cell-mediated immunity as assessed by skin test with Con A showed considerable depression.