Correlation of circulating antibody and cellular immunity with resistance against Cryptosporidium baileyi in broiler chickens.
The correlation of circulating antibody and cell-mediated immunity (CMI) with resistance to Cryptosporidium baileyi was studied using hormonal and chemical bursectomy in the one experiment and cyclosporin A in a second experiment. In Expt. 1, there was no correlation between antibody (confirmed by enzyme-linked immunosorbent assay) and resistance to infection as measured by body weight, gross lesions, morbidity, and mortality. Bursectomy altered antibody production, but not CMI, as measured by the delayed-type hypersensitivity skin reaction. In Expt. 2, cyclosporin A reduced CMI, but not antibody production. Chicks treated with cyclosporin A were more susceptible to C. baileyi (more severe respiratory disease) than untreated controls. Results suggested that CMI is more important in resistance to C. baileyi than circulating antibody.
Hatkin
J
J
Department of Poultry Science, Auburn University, Alabama 36849-5416.
Giambrone
J J
JJ
Blagburn
B L
BL
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000008:administration & dosage; D002060:Bursa of Fabricius / Q000276:immunology; D002645:Chickens / Q000276:immunology*; D003457:Cryptosporidiosis / Q000209:etiology / Q000276:immunology; D003458:Cryptosporidium / Q000276:immunology*; D006968:Hypersensitivity, Delayed; D007111:Immunity, Cellular; D011201:Poultry Diseases / Q000209:etiology / Q000276:immunology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan