Verification of immunosuppression in chicks caused by Cryptosporidium baileyi infection using Brucella abortus strain 1119-3

摘要

Humoral immune response of young chicks to Brucella abortus strain 1119-3 inoculation was monitored to verify the degree of immunosuppression caused by infection with Cryptosporidium baileyi. Young chicks (2-day-old) were orally inoculated each with 2 × 106 oocysts of C. baileyi, and then injected intramuscularly with 0.3 ml B. abortus strain 1119-3 containing 1 × 109 living organisms on day 14 postinoculation (PI). Serum samples were tested by plate agglutination test on day 17 PI onwards at an interval of 3-6 days over a period of 36 days. Infected chicks with the coccidium showed significantly lower antibody titers than those of uninfected controls (P C. baileyi infection in early life stage may predispose chicks easily to other potential poultry diseases.