Comparison of various culture methods (Skirrow medium, a blood-free medium and a filtration system enriched in Bolton and Preston broths) for isolation of Campylobacter spp. from raw meat samples

Abstract

We compared six procedures and investigated the optimal method for isolation of Campylobacter spp. from raw meat samples. Ninety-nine meat samples were enriched in Bolton broth and Preston broth, followed by plating on Skirrow, mCCDA, and blood agar (a membrane filter on its surface) media, respectively. Thirty-nine of 99 samples were positive and 71 Campylobacter were isolated by one or more methods. More than one species of Campylobacter were obtained in 8 (20.5 %) of 39 positive samples and two genotypes were yielded on the same medium (11 samples, 28.2 %) by pulsed-field gel electrophoresis (PFGE) genotyping. Enrichment by Preston broth was significantly better than by Bolton broth (P < 0.05). Moreover, the latter failed to detect Campylobacter jejuni strains. Skirrow medium was significantly less efficient than mCCDA medium and membrane filtration method (P < 0.05). Overall, the combination of PC (primary enrichment in Preston broth, followed by selective enrichment on mCCDA agar), PF (primary enrichment in Preston broth, followed by membrane filtration culture onto blood agar), and BF (primary enrichment in Bolton broth, followed by membrane filtration culture onto blood agar) methods provided the optimum isolation rate of Campylobacter spp.