INDUCTION OF PULMONARY IMMUNITY IN CATTLE BY THE ORAL-ADMINISTRATION OF ANTIGEN ENCAPSULATED IN ALGINATE MICROSPHERES

Mucosal immunity of the respiratory tract can be induced by the oral a dministration of antigens. Oral vaccines are easy to administer to a l arge number of animals. However, the antigens must be protected from t he acid and enzymes of the stomach. Encapsulation in polymeric microsp heres is one method to protect and enhance delivery of antigens to the inductive immune sites in the small intestine. In this study, ovalbum in was used as a test antigen encapsulated in alginate microspheres. O ral administration of ovalbumin in alginate microspheres resulted in t he appearance of IgA-secreting cells in the lungs of calves. The oral administration of vaccines to cattle could be a cost effective way to prevent economically important diseases, such as respiratory infection s, in cattle.