Characterization of campylobacter isolates from sheep with particular reference to enterotoxin production

ABSTRACT

C. jejuni subsp. jejuni, C. coli and C. laridis were isolated from apparently normal and diarrhoeic sheep with an incidence of 10% and 20%, respectively. C jejuni subsp. jejuni was the most predominant species with an overall incidence of 10.7%. All Campylobacter strains isolated from diarrhoeic animals were invasive to Hela cells and their cytotoxin produce degree [++] and [+++] of changes in Vero cells and titer of toxins were high [64-128]. C jejuni enterotoxin isolated from diarrhoeic sheep gave maximum secretion in rat ligated ileal loops. While enterotoxin of other strains evoked less fluid secretion in rat ligated ileal loops. SDS PAGE of heat labile enterotoxin extracted from isolated strains indicated protein profiles ranging from 49.3 to 59.3 KD. In immunized-challenged rats the fluid secretion was reduced by 70 to 80% less than the value for similar challenged unimmunized control rats. Antibody titers measured by ELISA showed four folds higher level than that in control animals