YERSINIA-ENTEROCOLITICA ENTEROTOXINS AND THEIR PATHOGENICITY IN RABBITS

The ileal loop response to study enterotoxin production by 8 strains o f Y. enterocolitica varied from 555 to 692 mu l/cm. The maximum fluid accumulation war: observed at 4 br time interval. At 121 degrees C for 15 min, 62.46% of enterotoxin activity was retained, but was complete ly lost in 5 strains when heated for 20 min. Heat stability of enterot oxin was further confirmed by infant mouse assay. Culture supernatants of all the strains were positive for skin permeability factor(PF) act ivity. Maximum PF activity was given by strain R(65) (352 mm(2)). Mark ed histopathological alterations in various tissues of rabbits were ob served after intravenous and intraluminal injections of enterotoxins.