Novel Campylobacter Isolation Method Using Hydrophobic Grid Membrane Filter and Semisolid Medium

Abstract

Culture procedures for isolation of thermophilic campylobacters from food matrices are complex, labor intensive, and time-consuming. Most available methods include the use of antibiotics as selective agents to prevent the growth of competing microflora. A simple procedure for isolation of thermophilic campylobacters after enrichment in Rosef's enrichment broth was developed using a hydrophobic grid membrane filter (HGMF) on semisolid medium (SSM). SSM contains no antibiotics, and the HGMF physically separates Campylobacter from the enrichment broth, allowing isolation based on differential motility. The HGMF-SSM method was compared to the Agriculture and Agri-Food Canada Food Safety Procedures Manual (FSPM-10) method (Isolation of Thermophilic Campylobacters from Fresh Pork, Beef Veal, Poultry and Ready-to-Eat Meat Products), which includes the use of selective antibiotics. During the initial study, after enrichment the HGMF-SSM method yielded pure cultures of campylobacters after 16 to 18 h (overnight) compared with 48 h for the FSPM-10 method. Ninety-four turkey samples collected at local retail stores and 38 frozen pig fecal samples were processed by both methods. Thirty-five samples (26.5%) were positive by the HGMF-SSM method; 24 (18.2%) of these positive samples contained Campylobacter jejuni and 11 (8.3%) contained Campylobacter coli. With the FSPM-10 method, 25 samples (18.9%) were positive: 21 (15.9%) with C. jejuni and 4 (3%) with C. coli. For a subsequent field study, only the HGMF-SSM method was used to isolate Campylobacter from 1,200 chicken samples and 454 turkey samples sold at retail. Analysis of five subisolates from various samples indicated that only one type of Campylobacter was recovered by the HGMF-SSM method, as ascertained by MICs for 10 antimicrobials, sequencing of the short variable region of the flaA gene, and fingerprinting based on amplified fragment length polymorphism. The absence of antibiotics in the SSM may explain the higher recovery of thermophilic campylobacters. The HGMF-SSM method resulted in improved isolation of campylobacters and is simpler, faster, cheaper, and less labor intensive than the FSPM-10 method. The recovery of one type of Campylobacter from the chicken samples may have important implications, particularly in epidemiological studies.

Investigation of germ caused by Guillain-Barré syndrome in poultry meat products in North West of Iran

“…17 The outbreak of Campylobacter species in chicken meat in other countries also suggests a contamination level of 30 to 90 percent. The contamination levels in different countries were as follows: Turkey with 92/8%, 18 Korea with 68/3%, 11 Canada with 62/4%, 12 Japan with 60%, 6 Ireland with 49/90%, 13 and Pakistan with 48%. 14 Despite having many studies reporting the prevalence of Campylobacter species contamination in poultry, there are few studies highlighting on the edible offal contamination to the bacteria.…”

“…12 Such high prevalence could be attributed to high temperature creating favorable conditions for the bacteria growth of and transferring of infection by insects. The overall results of this study on chicken meat and its edible offal contamination to Campylobacter species showed that a relatively high number of samples especially the liver were infected with this pathogen.…”

“…The prevalence of the infection in poultry given to the market have been reported to be 100% and lower incidences of other animals meat were also given. 5,6 Although there are many studies casting light on the prevalence of Campylobacter species among poultry in Iran, [7][8][9][10] and other countries including Korea, 11 Japan, 6 Canada, 12 Ireland, 13 Pakistan, 14 Belgium, 15 little data existed on the poultry meat biproducts infection including liver, gizzard and heart in Iran, therefore, the study aimed at evaluating the contamination of these products.…”

Antimicrobial Resistance in Campylobacter, Salmonella, and Escherichia coli Isolated from Retail Grain-Fed Veal Meat from Southern Ontario, Canada

“…The methods described in detail by Valdivieso-Garcia et al (44) were used for the isolation of Campylobacter. Briefly, 200 ml of the incubated Rosef's enrichment broth was used to inoculate a semisolid-medium plate with a quarter piece of Iso-Grid hydrophobic grid membrane filter (QA Life Sciences, Inc., San Diego, CA) and a 1-cm-diameter disk of filter paper (Schleicher & Schuell, Inc., Mandel, Guelph, Ontario, Canada).…”

An enhanced technique combining pre-enrichment and passive filtration increases the isolation efficiency of Campylobacter jejuni and Campylobacter coli from water and animal fecal samples

“…Conventional microbiology and selective culture techniques (Engberg et al, 2000;International Organization for Standardisation, 2005) -including various membrane filtration approaches (Bolton et al, 1988;le Roux and Lastovica, 1998;Mégraud, 1987;Steele and McDermott, 1984;Valdivieso-Garcia et al, 2007) have been developed for the isolation of Campylobacter spp. Selective media has been effective for the isolation of C. jejuni and C. coli (Engberg et al, 2000;Piersimoni et al, 1995); however, rarer and more elusive strains (e.g.…”