A preliminary study was conducted to compare the regional intestinal immune responses of neonatal calves inoculated with virulent or attenuated bovine coronavirus (BCV) to determine the cause of reported vaccine failures. A group of 9 newborn, colostrum-deprived calves was used; two calves were inoculated with attenuated virus, four calves were infected with virulent virus (including one naturally infected calf), and three calves were uninfected controls. Calves inoculated with virulent virus produced higher titers of BCV antibodies in the intestines than those inoculated with the attenuated virus. The failure of the calves to respond to the attenuated virus was apparently due to the inability of the virus to replicate to high titers. Spiral colon, ileum, and jejunum were found to be immunologically distinct; the highest anti-BCV antibody responses were detected in spiral colon, the primary site of infection, and involved all four isotypes of bovine immunoglobulins. The antibody response in ileum was lower than in spiral colon. The immune responses developed slowly in jejunum and were associated primarily with the IgG subtypes.
|Original language||English (US)|
|Number of pages||11|
|Journal||Comparative Immunology, Microbiology and Infectious Diseases|
|State||Published - May 1994|
Bibliographical noteFunding Information:
Acknowledgements--We thank Professor Hans Fey, University of Bern, Switzerland, for providing polyvalent antisera against bovine immunoglobulin classes and subclasses. This project was funded in part by Minnesota Agricultural Experiment Station. Published as contribution no. 18206 of the series of the Minnesota Agricultural Experiment Station. We thank Lin Gelbman and Paul Vrostos for technical assistance.
- Bovine coronavirus
- calf scours
- enteric disease
- mucosal immunity
- regional immunity