Use of a live oral vaccine to immunize turkeys against erysipelas.

Turkeys were vaccinated via the drinking water with a commercial live erysipelas vaccine licensed for use in swine. The vaccine provided partial protection against challenge with a virulent isolate of the same serotype. Efficacy was determined by comparing the mortality rates of vaccinates with nonvaccinates. Two vaccine treatments (2 weeks apart) with the live vaccine, each treatment consisting of two doses (4 x 10(9) organisms/dose), were effective in inducing protection. Turkeys vaccinated similarly with live vaccine doses containing 10(5) or 10(7) organisms/dose were not protected against challenge. A bacterin-production strain of Erysipelothrix rhusiopathiae (EW-2) was not effective as a live vaccine. Turkeys vaccinated subcutaneously with a commercial bacterin, the current immunoprophylactic agent for erysipelas control, were protected against challenge. These results indicate the potential usefulness of an orally administered live vaccine for erysipelas control in turkeys.