Comparison of Selective Enrichment Broths for Isolation of Campylobacter jejuni/coli from Freshly Deboned Market Chicken

Abstract

The efficiency of Brucella broth supplemented with vancomycin-trimethoprim-polymyxin B (VTP) at the same concentration as Skirrow agar and bacitracin-colistin-cephalothincycloheximide-novobiocin (BCN) at the same concentration as Butzler agar was evaluated in the recovery of Campylobacter jejuni/coli from fresh retail chicken. Ninety-two samples were acquired from retail markets in Guadalajara, Mexico, and analyzed by enrichment in VTP and BCN broths, each streaked on Skirrow and Butzler agars. Thirty-three (36%) of the samples were positive by any route of analysis. The recovery of Campylobacter (19.6% in VTP alone, 25.0% in BCN, and 35.9% in VTP+BCN) was enhanced by simultaneously using two instead of only one enrichment broth, especially when VTP broth was used (p<0.05). There was an elevated rate of samples containing Campylobacter which gave false-negative results on VTP (45.2% of false-negatives) and on BCN (30.3%). While isolation on Butzler agar showed a similar distribution between samples derived from VTP or BCN broths, Skirrow agar was effective only when the inoculum was derived from BCN broth. Our results indicated that vancomycin-trimethoprim-polymyxin B mixture was not a suitable agent for use in an enrichment-plating procedure to recover Campylobacter from chicken, and that by simultaneously using two enrichment broths the ability to recover Campylobacter was enhanced significantly.