Figure 10. Antibody responses in nasal lavages however were found in orally-, but not transtracheally-, inoculated calves.

Specific antibody levels were measured in nasal lavage fluids obtained from calves inoculated with M. bovis. Samples were collected at necropsy from calves inoculated by the oral route (N = 8; 14 days post-infection, except for one calf inoculated with M. bovis by the oral route which had to be euthanized at 10 days post-infection), the transtracheal route (N = 5; 14 days post-infection), and from control calves (N = 8; 14 days post-sham inoculation). Data are expressed as the mean ± SD of the optical density (O.D.) adjusted for the total amount of immunoglobulin (Ig), calculated as the optical density for M. bovis-specific Ig/total Ig (µg/ml) in the sample for each isotype. ^abSuperscript letters indicate significant (P<0.05) differences between groups.