Indian Journal of Poultry Science

Humoral and celluar inunune response was studied in Japanese quail following S. typhimurium infection. The humoral inunune response, as detected by tube agglutination test, revealed a gradual increase in the agglutinating antibodies starting from 1st week reaching to the highest titre of 1: 1280 at 3 weeks. This was followed by a drop in titre but the infected birds remained seropositive upto the end of observation period (6 weeks). The cell mediated immune response was assessed by skin hypersensitivity reaction following intradermal injection of sonicated antigen (S. typhimurium) in the foot-pad at 21 days of infection. A marked increase in thickenss of the test site was recorded, which on microscopic examination was found to be the result of congestion, serofibrinous exudate mixed with large number of heterophils and a few lymphocytes at 24 hours post-injection, while at 48 hours, there was increase in the number of lymphocytes.