CAMPYLOBACTER-JEJUNI-COLI METHODOLOGY OF ISOLATION AND POSSIBLE INTERFERING FACTORS IN PRIMARY CULTURE

The prevalence of Campylobacter jejuni and Campylobacter coli was inve stigated in 64 samples of fresh retail chicken purchased from commerci al slaughterhouses located in Brazil. Campylobacter spp. were isolated from 40 (62.5%) of 64 analyzed samples. The strains biotyped accordin g to Lior were classified as C. jejuni biotypes I and II, and C. coli biotypes I and II. The efficiency of different procedures for recoveri ng Campylobacter spp. from chicken carcasses was tested. The enrichmen t procedure was significantly less effective than direct plating (P < 0.05), detecting 19 of 40 (47.5%) as opposed to 38 of 40 (95%) positiv e samples. Using direct plating the efficiency of Blaser's selective s upplement was significantly more effective (P < 0.05) than Skirrow's s elective supplement. To verify which factors could be affecting Campyl obacter spp. growth in enrichment broth, the pH was measured after inc ubation for 48 h at 42 degrees C and lactobacilli, coliforms, and ente rococci were enumerated. Most of the Campylobacter-negative samples pr esented high levels of indicator microorganisms, which may have hinder ed the recovery of Campylobacter spp. during the enrichment procedure.