Lambs from suckling ewes vaccinated with the K99 antigen were resistant to challenge with K99-positive enteropathogenic Serum and colostrum from these ewes were compared with samples from control ewes to establish methods for monitoring vaccination and to determine the mechanism of protection.

Vaccination stimulated production of K99 antibodies. These could be detected by an indirect haemagglutination test and a haemagglutination-inhi-bition test. Antiglobulin and gel-diffusion tests were less reliable. Experiments with brush-border cells from calf intestine showed that the antibodies were associated with anti-adhesive activity. The antibodies were predominantly IgG and did not neutralise the activity of heat-stable enterotoxin. It was concluded that neutralisation of the adhesive properties of the K99-posi-tive by colostral antibodies significantly contributed to the resistance of the lambs from vaccinated ewes.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error