Vaccination of cattle with Brucella abortus strain 19 administered by differing routes and doses.

As a result of brucellosis control problems in large Florida dairy herds the use of Brucella abortus strain 19 vaccination has been re-examined. Cattle were vaccinated with different doses of Brucella abortus strain 19 administered by different routes. On the whole, the route of administration was found to have little influence on the efficacy of the vaccine, although the efficacy of vaccine administered orally was difficult to assess. The reduced doses given subcutaneously was selected as the preferred method for adult cattle vaccination.