RESPONSE OF CALVES TO LUNG CHALLENGE EXPOSURE WITH PASTEURELLA-HAEMOLYTICA AFTER PARENTERAL OR PULMONARY IMMUNIZATION

  • 1 January 1980
    • journal article
    • research article
    • Vol. 41  (11) , 1773-1778
Abstract
In 3 experiments, calves were vaccinated by intrabronchial or s.c. injection of formalinized P. haemolytica. Immunization was evaluated by assessing the clinical and pathologic responses to pulmonary challenge exposure with live homologous bacteria. Serum and bronchoalveolar washings were titrated for antibody by indirect (antiglobulin) bacterial agglutination. Response to challenge exposure was determined by increased rectal temperature and faster respiratory rate. In all experiments, the most obvious clinical change occurred in challenge-exposed calves which were vaccinated by the s.c. injection of killed P. haemolytica with added adjuvant. Macroscopic pulmonic lesions were recorded most frequently in calves vaccinated by this route. In all instances, immunization resulted in elevated anti-P. haemolytica titers in lung and serum.