Incidence ofYersinia enterocoliticaand RelatedSpecies in Some Fish, Meat and Meat Productsin India

Abstract

A total of 38 samples, including 15 fish products, 11 meat products from retail shops and 12 pork products from a factory place, was examined for the presence of Yersiniaspecies. Six well-known isolation protocols were used. A two-stage enrichment procedure including 48 h incubation of sample homogenates in brain heart infusion at 8–10°C followed by incubation in sorbitol bile broth at 22–28°C for 48 h recovered the highest number ofYersiniaspp on cefsulodin–irgasan–Novobiocin agar. A total of 302 isolates, consisting mainly ofY intermedia(74, 41, 25),Y pestis(4, 8, 23),Y enterocolitica(5, 6, 5) andY pseudotuberculosis(0, 5, 1) was obtained from retail fish and meat products and from factory oriented pork products, respectively. Many of the isolates were not identified to species level because of their unusual biochemical reactions. None of theY enterocoliticaisolates contained the virulence plasmid as evidenced by their biotype (5 and 1) and inability to bind crystal violet.