OCCURRENCE OF CLOSTRIDIUM-PERFRINGENS IN UNCOOKED COCK-TAIL SAUSAGES AT RETAIL LEVEL AND ITS PUBLIC-HEALTH SIGNIFICANCE

Samples (127) of uncooked cock-tail sausages were examined for Clostri dium perfringens using iron-milk medium and sulphite-polymyxin-sulfadi azine (SPS) agar as selective enumeration medium. Of these 74.8% conta ined the vegetative cells of C. perfringens with iron-milk-medium, whe reas only 65.3% of the samples were positive using SPS agar. About 35% samples did not reveal C. perfringens on SPS agar by direct inoculati on from 10-fold serial dilutions. The MPN (Most Probable Number) index of C. perfringens with iron-milk medium ranged from log 2.96/g to log 7.30/g. Average counts on SPS agar were in the range of log 2.71/g an d log 5.11/g. About 5% of the samples contained enough bacteria to pro duce food poisoning. The frequency of distribution approximately follo wed Poisson equation with mu = 1.94. Of the total isolates, 36% were e ntero-toxigenic by increased capillary permeability test.