Pasteurella challenge and ELISA serology evaluation of broiler breeders vaccinated with live cholera vaccine

Broiler breeder pullets were vaccinated against fowl cholera at 10 and 20 wk of age using a live PM-1 Pasteurella multocida vaccine administered by wing web stick. Antibody production for P. multocida was measured at vaccination and at 1-4-wk intervals following vaccination by enzyme-linked immunosorbent assay. Groups of vaccinated birds were challenged at 23 and 32 wk of age. Two doses of a live PM-1 P. multocida vaccine protected broiler breeder hens against virulent challenge up to 32 wk of age when measured antibody levels had a range of 1951-4346 and a geometric titer of 3000.