Prevalence and antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from raw chicken meat and human stools in Korea

Prevalence of Campylobacter in raw chicken meat and human stools and subsequent antibiotic resistance profiles of the pathogenic isolates obtained from 2000 through 2002 were investigated. Campylobacter jejuni and Campylobacter coli were isolated from 570 of the 923 raw chicken meat samples collected from traditional markets, large retail stores, or department stores in Korea, resulting in the isolation rate of 61.8%. A total of 579 Campylobacter isolates were obtained from raw chicken (36.3% for C. jejuni and 26.4% for C. coli) with the average population of 335.6 CFU/g. From 513 human stool samples, 15 isolates of Campylobacter were detected. Seasonal variation in the quantification of C. coli was not noticeable throughout the year, while the isolation rate of C. jejuni was the highest in September through October (840 CFU/g) followed by that of July through August and May through June in decreasing order, showing a significant seasonal effect (P < 0.05). Contamination of Campylobacter was more severe in raw chicken meat sold in traditional markets than in those sold in large retail stores and department stores. Prevalence of Campylobacter in raw chicken sold in traditional markets was significantly influenced by seasonal changes (P < 0.05), whereas the samples obtained from other places was less affected by the seasonal changes. Susceptibilities of the 594 chicken isolates to ciprofloxaxin, chloramphenicol, erythromycin, kanamycin, nalidixic acid, and tetracycline were determined by an E-test. Campylobacter isolates were the most resistant to nalidixic acid (91.4%) followed by ciprofloxaxin (87.9%), tetracycline (87.2%), kanamycin (30.6%), erythromycin (19.4%), and chloramphenicol (1.3%). Human isolates showed a similar resistance to the six antibiotics tested. The proportion of Campylobacter isolates with multidrug resistance to four or more antimicrobials obtained from 2000 through 2002 ranged from 28 to 43.5%, indicating that it could be a serious health-threatening factor. This study suggests that it is prudent to establish an effective National Monitoring Program in Korea for the prevention and control of Campylobacter spp.     

Antimicrobial resistance among Campylobacter jejuni isolated from raw poultry meat at retail level in Denmark

Campylobacter jejuni isolated from raw poultry meat collected at retail shops in Denmark in the period 1996-2003 were tested for susceptibility to seven antimicrobial agents. The food samples consisted of raw chicken meat and other raw poultry meat of domestic or imported origin. The highest levels of resistance among C. jejuni were observed for tetracycline, nalidixic acid and ciprofloxacin, whereas macrolide resistance was rarely detected. C. jejuni originating from other poultry meat (mainly duck and turkey meat) exhibited the highest occurrences of antimicrobial resistance monitored; approximately one third of the isolates were tetracycline resistant (N=100). Among chicken meat isolates, the occurrence of tetracycline resistance was significantly higher (P<0.005) in C. jejuni isolated from imported chicken meat (N=88) than in C. jejuni from Danish chicken meat (N=367). The same tendency was observed for chloramphenicol, nalidixic acid and ciprofloxacin (P<0.05). The trends in resistance in the period 1996-2003 among C. jejuni isolates from chicken meat indicate a decrease in the occurrence of resistance towards fluoroquinolones. This may be due to reduced application of fluoroquinolones for food animals. Monitoring of the occurrence of antimicrobial resistance in C. jejuni isolated from raw uncooked poultry has been performed on a yearly basis since 1996, thus providing useful insight into consumer exposure to antimicrobial-resistant C. jejuni.     

Prevalence and antimicrobial resistance of Campylobacter isolated from retail raw chicken and beef meat, Tehran, Iran

Campylobacter spp. is a leading cause of human diarrhea. The common source of infection is contaminated food, particularly poultry. The veterinary use of antimicrobial drugs has been suggested to be largely responsible for resistance in human isolates of this zoonotic pathogen. From April to October 2004, 241 samples of chicken and beef meat for sale in retail outlets in Tehran (Iran) were analyzed for the presence of Campylobacter. Totally, 88 (36.5%) Campylobacter strains were isolated. Campylobacter was isolated from a significantly larger number of chicken (63%) than beef (10%) meat (P < 0.0001). Susceptibilities of 72 strains were determined for eight antimicrobial drugs using the disk diffusion assay. Resistance to nalidixic acid was the most common finding (75%), followed by resistance to ciprofloxacin (69.4%), tetracycline (45.8%), amoxicillin (11.1%), streptomycin (4.2%), chloramphenicol (2.8%) and gentamicin (1.4%). None of the isolates was resistant to erythromycin. Multidrug resistance was seen in 75% of the Campylobacter strains.     

Antimicrobial resistance and molecular subtyping of Campylobacter jejuni and Campylobacter coli from retail meats

Campylobacter isolates (n = 297; 202 C. jejuni and 95 C. coli isolates) recovered from 2,513 retail meat samples (chicken breasts, ground turkey, ground beef, and pork chops) were examined for antimicrobial susceptibility. The isolates were further analyzed for genetic relatedness by pulsed-field gel electrophoresis (PFGE) using SmaI and KpnI restriction enzymes, and a subset of isolates (n = 174) were subtyped by multilocus sequence typing (MLST). The resistance most frequently observed was that to doxycycline (27.6%), followed by ciprofloxacin (13.8%) and erythromycin (6.4%). All isolates were susceptible to gentamicin and meropenem. C. coli showed higher resistance to doxycycline than did C. jejuni (42.1 versus 20.8%) and lower resistance to ciprofloxacin than did C. jejuni (10.5 versus 15.3%). Erythromycin resistance was only observed in C. coli. PFGE using SmaI plus KpnI digestion generated 168 clusters from 297 isolates: 115 from C. jejuni and 53 from C. coli. MLST revealed 44 sequence types (STs) under 10 clonal complexes from 120 C. jejuni and 27 STs under two clonal complexes from 54 C. coli. There was a positive association between PFGE and STs; however, PFGE showed greater discriminatory power than MLST. Subtyping data did not correlate with antimicrobial resistance phenotypes.     

Species identification by genotyping and determination of antibiotic resistance in Campylobacter jejuni and Campylobacter coli from humans and chickens in Sweden

Campylobacter is today the most common cause of human bacterial enteritis in Sweden, as well as in most other industrialized countries. Common sources of infection are undercooked chicken meat, unpasteurized milk and contaminated drinking water. One aim with our present study was to identify the species Campylobacter jejuni and Campylobacter coli strains from humans and chickens using a polymerase chain reaction/restriction enzyme analysis (PCR/REA) method, as well as traditional hippurate hydrolysis test. Another aim was to investigate the antibiotic resistance pattern of the human domestic C. jejuni/C. coli isolates from infected patients and isolates from healthy Swedish chicken, as well as isolates from humans infected abroad. If discrimination between C. jejuni and C. coli was based on testing for hippurate hydrolysis, 95% of the human domestic strains and 88% of the chicken strains were identified as C. jejuni. Based on genotyping by PCR/REA, 100% of the human domestic strains and 98% of the chicken strains were attributed to C. jejuni. The E-test and disc diffusion methods were used for phenotypic antibiotic resistance studies. The two methods gave similar results. Most Swedish C. jejuni/C. coli isolates both from humans and chickens were sensitive to doxycycline and erythromycin, which are antibiotics used to treat human infection. Only 7% of the human domestic strains and 2% of the chicken strains were resistant to the quinolones tested. As a comparison, more than 94% of strains isolated from travelers to Asia and southern Europe showed antibiotic resistance to one or more drugs.     

Prevalence, numbers, and subtypes of Campylobacter jejuni and Campylobacter coli in uncooked retail meat samples

A national quantitative survey of Campylobacter jejuni and Campylobacter coli in 1,011 uncooked retail meat samples (beef, unweaned veal, chicken, lamb and mutton, and pork) was undertaken from August 2003 to June 2004 to establish baseline proportionality data. The presence, number, and type of Campylobacter present in each sample was assessed. Prevalences of C. jejuni and C. coli were 89.1% in chicken, 9.1% in pork, 6.9% in lamb and mutton, 3.5% in beef, and 10% in unweaned veal. C. jejuni was identified in the majority of positive samples (246 of 259). In chicken samples positive for C. jejuni, 40.2% had counts of <0.3 most probable number (MPN)/g, 50.5% had 0.3 to 10.0 MPN/g, 8.8% had 10.1 to 50.0 MPN/g, and 0.5% had 110 MPN/g. In other meats (49 samples), Campylobacter counts were < or = 0.3 MPN/g, except for one unweaned veal sample at > 10.9 MPN/g. Penner serotyping and SmaI macrorestriction genotyping using pulsed-field gel electrophoresis with 247 isolates revealed 17 Penner serotypes and 56 electrophoresis profiles. Seven Penner serotypes (HS1 complex, 2, 4 complex, 6, 11, 27, and 42) were represented by 10 or more isolates from chicken. When data from both typing methods were combined, 62 sero-genotypes were generated. In a comparison of these sero-genotypes with historical data for isolates from human cases, 71% of the beef isolates, 50% of the lamb and mutton isolates, 50% of the pork isolates, 41% of the chicken isolates, and 25% of the unweaned veal isolates were common to both sources. These results provide baseline proportionality profiles of Campylobacter in these five meats and will facilitate exposure assessment in combination with other information such as consumption data and subsequent quantitative risk assessment.     

Prevalence of Campylobacter spp. on chickens from selected retail processors in Trinidad

The prevalence of Campylobacter in chicken sold at “pluck shops” in Trinidad was investigated. “Pluck shops” were classified as medium or low sale and samples were collected from 6 counties in Trinidad. Swab samples of cloacae of birds before slaughter and the carcass surfaces after processing, were plated on blood-free Campylobacter agar base containing CCDA Selective Supplement and plates incubated at 42°C in 8% CO₂ for 48 h. Of the 645 of each type of sample collected, 517 (80.2%) and 541 (83.9%) of the cloacal and carcass samples, respectively, were positive for Campylobacter spp. Campylobacter was recovered from 519 (81.1%) of 640 samples taken from medium-sale shops and from 539 (82.9%) of 650 samples from low-sale shops. The prevalence of Campylobacter was statistically significantly different when related to the length of time a bird is kept in the shop (p=0.03) and the location of carcass for sale (p=0.02). The frequency of Campylobacter in chickens sold at “pluck shops” in Trinidad is high and poses a potential health risk to the consumer. The need to institute sanitary conditions at these establishments cannot be over-emphasized.     

Prevalence and antibiotic resistance of Campylobacter spp. isolated from chicken meat, pork, and beef in Korea, from 2001 to 2006

A total of 770 samples of retail raw meat were examined for the presence of Campylobacter spp. The samples were obtained randomly from 232 retail stores in Korea from September 2001 to April 2006. The highest contamination rates were observed in chicken meat (220 181.4%] of 270 samples), whereas the rates of contamination in pork and beef were extremely low (1.6 and 1.2%, respectively). The antibiotic-resistant patterns of the 317 Campylobacter isolates were examined by the agar dilution method. Resistance to doxycycline was the most common (97.5%), followed by ciprofloxacin (95.9%), nalidixic acid (94.6%), tetracycline (94.6%), enrofloxacin (84.2%), and erythromycin (13.6%). All Campylobacter isolates from the retail raw meat were resistant to at least one of the six antibiotics tested, and 296 isolates (93.4%) showed multidrug (four or more antibiotics) resistance. This demonstrates that the multidrug-resistant Campylobacter species are widespread in meats in Korea. Therefore, further investigations will be needed to determine appropriate methods for eliminating Campylobacter contamination in industrial chicken production and food chains.     

Metronidazole resistance in Campylobacter jejuni from poultry meat

The occurrence of metronidazole resistance was investigated among Campylobacter jejuni in raw poultry meat collected from supermarkets. MICs were determined by the agar dilution procedure in the testing range of 3 to 60 microg/ml metronidazole. The MICs showed a bimodal distribution with a significant proportion of metronidazole-resistant isolates among C. jejuni from raw broiler and turkey meat. Metronidazole resistance occurred most frequently among turkey meat isolates (P < 0.005). This is the first report of foodborne bacteria carrying metronidazole resistance.     

Antimicrobial resistance of Salmonella in raw retail chickens, imported chicken portions, and human clinical specimens

Salmonella isolates from raw, chilled, retail chickens (n = 434) sampled between 1998 and 2000 were tested for resistance to 12 antibiotics. Of 23 salmonellas isolated, 30% were susceptible and 30% were resistant or intermediately resistant to one antibiotic, 26% to two, and 13% to four or more. One Salmonella Saint-Paul and two Salmonella Typhimurium isolates were resistant to more than four antibiotics. Highest resistance rates were sulfonamide (52%), streptomycin (26%), tetracycline (22%), and ampicillin (17%). Isolates (n = 27) from frozen chicken portions (n = 150) imported from Brazil and Thailand (generally for manufacturing and catering) were also tested. Brazilian salmonellas showed no multiple resistance, but an isolate of Salmonella Virchow from Thai chickens was resistant to two antibiotics. This compared with 39% resistance to two or more antibiotics in nonimported isolates. Resistance patterns of both sets of chicken isolates were compared with human fecal clinical isolates (n = 274) submitted for routine examination at this hospital, and a greater similarity was found between the clinical and local isolates than with imported salmonellas. Sulfonamide resistance in imported salmonellas was lower than that of nonimported and clinical isolates. Resistance to one or more antimicrobial was found in 70% of nonimported raw retail chickens, 52% of imported chicken breast fillets, and 84% of human fecal isolates. Multiple resistance (to four or more antibiotics) is a much more limited problem.     

Prevalence, antibiotic resistance, and molecular characterization of Salmonella serovars in retail meat products

The prevalence of Salmonella was determined in chicken meat (n = 26), beef (n = 49), and pork (n = 56) collected from wholesale markets, retail stores, and traditional markets in Seoul, South Korea, in 2009. Antibiotic resistance was assessed, and the molecular subtypes of Salmonella isolates were ascertained using an automated repetitive sequence-based PCR (rep-PCR) system (DiversiLab). A total of 18 Salmonella strains were isolated from 17 of 131 samples: 16 strains from each of 16 samples and 2 strains from the same pork sample. The prevalence of Salmonella from the retail meats was 2.0% in beef, 8.9% in pork, and 42.3% in chicken meat. Among 10 different serotypes, Salmonella enterica Panama was recovered from a beef sample, and Salmonella London and Salmonella Montevideo were the predominant serotypes from pork and chicken meat, respectively. The highest antibiotic resistance observed was to erythromycin (100%) followed by streptomycin (22.2%) and tetracycline and chloramphenicol (16.7%). Of the 18 isolates, 5 (27.8%) were resistant to two or more antibiotics, and 1 isolate from chicken meat was resistant to eight antibiotics, including cephalosporins. Differentiation between all of the Salmonella isolates except between Salmonella Montevideo and Salmonella London was successfully performed with the automated rep-PCR system, indicating that it can be added to the toolbox for source tracking of foodborne pathogens associated with outbreaks.     

High level of antimicrobial resistance in Campylobacter jejuni isolated from broiler chickens in Estonia in 2005 and 2006

The development of antimicrobial resistance in Campylobacter jejuni and Campylobacter coli is a matter of increasing concern. Because campylobacteriosis is transmitted to humans usually via food of animal origin, the presence of antimicrobial-resistant campylobacters in broiler chickens has important public health implications. The aim of our study was to analyze resistance patterns of C. jejuni isolated from fecal samples collected at a large Estonian chicken farm, from cecal contents collected at slaughterhouses, and from meat samples collected at the retail establishments in 2005 and 2006. A total of 131 C. jejuni isolates were collected over a 13-month period and tested by the broth microdilution VetMIC method (National Veterinary Institute, Uppsala, Sweden) to determine the MICs of various antimicrobials. Resistance to one or more antimicrobials was detected in 104 (79.4%) of the 131 isolates. High proportions of the isolates were resistant to enrofloxacin (73.3%) and nalidixic acid (75.6%). Multidrug resistance (resistance to three or more unrelated antimicrobials) was detected in 36 isolates (27.5%), all of which were resistant to enrofloxacin. Multidrug resistance was significantly associated with enrofloxacin resistance (P < 0.01), and the use of enrofloxacin may select for multiresistant strains.     

Prevalence of Campylobacter and Salmonella in raw chicken on retail sale in the republic of Ireland

To assess the current risks to consumers from Campylobacter and Salmonella in raw chicken products sold in the Republic of Ireland, a retail survey was undertaken to define their prevalence. Samples (n = 510) were analyzed using protocols based on ISO 10272-1:2006 and ISO 6579:2002. Processor codes on pack labels showed that 67% of samples were produced in the Republic of Ireland and 25% in the United Kingdom. Salmonella was present in 5.1% of samples, but the eight serovars found caused less than 7% of human salmonellosis reported in the Republic of Ireland. The results suggest that on-farm controls to limit Salmonella infection of broilers have been successful and that in Ireland raw chicken is not a significant cause of salmonellosis in humans. The overall prevalence of Campylobacter spp. was 84.3%. Isolation by the ISO method found 52.7% of samples to be positive, but overgrowth by contaminants was frequently evident. Therefore, in addition to enrichment, an homogenized sample was plated directly onto modified charcoal cefoperazone deoxycholate agar, and this detected a further 31.6%. Speciation of isolates (n = 426) determined that 67% were Campylobacter jejuni and 32% were Campylobacter coli. These species are the most common cause of campylobacteriosis in man. The results indicate that there is a need for poultry producers to introduce interventions to minimize the exposure of consumers in the Republic of Ireland to Campylobacter spp., as has been successfully done for Salmonella.     

Prevalence and characterization of Campylobacter jejuni isolated from pasture flock poultry

The growing interest in organic and natural foods warrants a greater need for information on the food safety of these products. In this study, samples were taken from 2 pasture flock farms (N = 178; feed, water, drag swabs, and insect traps), pasture flock retail carcasses (N = 48) and 1 pasture flock processing facility (N = 16) over a period of 8 mo. A total of 105 Campylobacter isolates were obtained from 53 (30%), 36 (75%), and 16 (100%) samples from the farms, retail carcasses, and processing facility, respectively. Of the 105 isolates collected, 65 were C. jejuni, 31 were C. coli, and 9 were other Campylobacter spp. Using PCR, the C. jejuni isolates were further analyzed for virulence genes involved in colonization and survival (flaA, flaC, cadF, dnaJ, racR, cbrR), invasion (virB11, ciaB, pldA), protection against harsh conditions (sodB, htrA, clpA), toxin production (cdtA, cdtB, cdtC), siderophore transport (ceuE), and ganglioside mimicry (wlaN). In addition, the short variable region of the flaA locus (flaA SVR) was sequenced to determine the genetic diversity of the C. jejuni isolates. The flaA SVR diversity indices increased along the farm to carcass continuum. PCR-based analysis indicated a low prevalence of 5 genes involved in colonization (dnaJ, ciaB, pldA, racR, virB11). The results of this survey indicate that the prevalence of Campylobacter on organic retail carcasses is similar to prevalence reports of Campylobacter on conventional retail carcasses. However, the genetic diversity of the flaA SVR genotypes increased along the farm to carcass continuum that contrasted with conventional poultry studies. PRACTICAL APPLICATION: Campylobacter jejuni is a leading cause of foodborne illness with poultry and poultry products being leading sources of infection. Free-range and pasture flock chickens are becoming more popular; however, there is an inherent biosecurity risk that can increase the prevalence of foodborne pathogens in these flocks. This study aimed to determine sources and characterize C. jejuni isolated from pasture flocks.     

Prevalence and numbers of Salmonella and Campylobacter spp. on raw,whole chickens in relation to sampling methods

Salmonella and Campylobacter continue to be major foodborne pathogens and raw poultry is considered to be an important source of these bacteria. In this study, the prevalence and numbers of Salmonella and Campylobacter spp. in relation to isolation/sampling methods were determined in 241 whole raw chickens purchased from retail outlets in England during the winters of 1998/1999 (101 chickens) and 1999/2000 (140 chickens). The packaging of the 140 chickens was also examined for the presence of the above pathogens. The prevalence and numbers of enterococci were examined in 21 of the 101 chickens. In total, Salmonella and Campylobacter spp. were present in 25% and 83% of the chickens, respectively. Salmonella were isolated from a sample representing both the inside and outside of the packaging in 19% of the chickens, while the corresponding figure for Campylobacter spp. was 56%. Both of these pathogens were isolated from the outside of the packaging in 6% of the chickens. Salmonella was more frequently isolated from samples containing chicken skin in comparison with those containing carcass-rinse fluid only. Two chickens (0.8%) were positive for Salmonella by direct enumeration methods with contamination levels of log10 3.8 and 4.5 colony forming units (cfu) per carcass, respectively. The most prevalent serotypes were S. Hadar, S. Enteritidis and S. Indiana and two different serotypes were identified in 5/20 salmonella-positive chickens. Resistance to at least one antibiotic was found in 70% of the strains, 46% were multiresistant (resistant to > or = four drugs) and 52% showed a lowered susceptibility to ciprofloxacin. The likelihood of isolating Campylobacter spp. from neck-skin, carcass-rinse or carcass-rinse plus whole skin samples was similar, Campylobacter spp. were found in higher levels in carcass-rinse or carcass-rinse plus whole skin samples than in neck-skin. The log10 cfu of Campylobacter spp. were 2.70-4.99 in 18% of the chickens and 5.00-6.99 in 20%. Campylobacter isolates (425) comprised Campylobacter jejuni (98%) and C. coli (2%) and 98 different sero/phagetypes of these two species were identified. Resistance to at least one antibiotic was found in 73% of the strains and 13% were multiresistant. Thirteen percent of the strains showed lowered susceptibility to ciprofloxacin, while 4.9% were resistant to erythromycin. Vancomycin-resistant enterococci (VRE), able to grow on agar containing 15 mg l(-1) vancomycin (VRE15), were present in 19 chickens. The log10 cfu of VRE15 was 2.90-3.99 in 10 chickens and between 4.00 and 4.99 in two chickens. The data presented here contribute to risk assessment and highlight the need to continue to emphasise the safe handling of raw retail poultry.     

Colonizing capability of Campylobacter jejuni genotypes from low-prevalence avian species in broiler chickens

Genetic variations in Campylobacter jejuni or host factors result in low prevalence rates among nonchicken poultry species. The objective of this study was to determine the colonizing potential, in broiler chickens, of C. jejuni that was recovered from low-prevalence avian species. Twenty-day-old Campylobacter-negative broiler chicks were inoculated by oral gavage with genetically different primary isolates of C. jejuni recovered from squab, duck, or chicken. Serial sampling and microbiologic testing of ceca were used to determine the level of colonization and the prevalence of positive chickens. All isolates were recovered from chickens by 10 days postinoculation. The C. jejuni strains recovered from challenged birds were genetically identical to the inoculated strains. By 10 days postinoculation, treatment groups inoculated with duck or control chicken isolates were 100% positive. The level of colonization by the squab isolate on day 2 postinoculation was significantly less than the duck or chicken isolates and had not colonized all birds by day 10 postinoculation.     

Salmonella and Campylobacter in United Kingdom retail raw chicken in 2005

The United Kingdom Food Standards Agency commissioned a survey of Salmonella and Campylobacter in raw, whole chickens at retail in Wales and Northern Ireland between March and December 2005 to measure the baseline prevalence rates of these two significant pathogens. In total, 877 retail samples were examined for Campylobacter and Salmonella by enrichment methods. Overall contamination rates of 70.2% for Campylobacter and 4.0% for Salmonella were found. There was a statistically significant difference in Campylobacter rates between fresh and frozen samples, with fresh samples having a higher rate. There was no statistically significant difference between samples taken from retailers and butchers. Campylobacter was significantly more common in Northern Ireland than in Wales. Salmonella was significantly more common in Wales. The findings indicate the need for further investigation to explore why measures that have been successful in reducing Salmonella in the United Kingdom in recent years have failed to contribute to the control of Campylobacter. Identifying the factors responsible could lead to the introduction of more effective controls throughout the industry.     

Prevalence and diversity of Campylobacter jejuni in pig herds on farms with and without cattle or poultry

The prevalence and diversity of Campylobacter jejuni was investigated in pig herds on farms with and without cattle or poultry production. A bacteriological screening of pig cecal samples from 247 finisher herds was carried out at the slaughter-house. Subsequently, a follow-up study was conducted in 24 herds (either with or without prior C. jejuni isolation from pigs) in which fecal samples were collected from pigs and, if present, cattle and poultry. Samples were analyzed for presence of Campylobacter, and subsequent analysis included species identification, serotyping, and, for selected strains, pulsed-field gel electrophoresis typing. In the slaughterhouse screening, C. jejuni was isolated from pigs in 21 (8.5%) herds, but no significant difference in prevalence was found between herd types (pigs, pigs and cattle, pigs and poultry). At the slaughterhouse, C. jejuni and Campylobacter coli prevalence in pigs was 2.3 and 90.1%, respectively. In the follow-up study, herd prevalence of C. jejuni was 8.3%, whereas C. jejuni and C. coli were isolated from 0.8 and 92.0% of pigs, respectively. In mixed production herds, C. jejuni predominated in cattle (42.7%) and poultry (31.6%), whereas C. jejuni was only isolated from 1.3 to 2.5% of pigs in these herds. There were no significant differences in C. jejuni or C. coli prevalence in pigs, cattle, and poultry between herds with and without prior C. jejuni isolation at the slaughterhouse. Pulsed-field gel electrophoresis typing did not yield evidence of C. jejuni transmission between cattle or poultry and pigs in mixed production herds. In contrast, pulsed-field gel electrophoresis analysis showed indistinguishable serotypes of C. coli in pigs and cattle in two herds. Verification of C. jejuni-positive pig samples showed that individual pigs can excrete high levels of C. jejuni and that mixed infection with C. jejuni and C. coli was common in C. jejuni-positive pigs. The results of our study suggest that transmission of C. jejuni between pigs and cattle or poultry in mixed production herds occurs infrequently. Detection of indistinguishable C. coli isolates in two herds, however, might indicate the existence of low-level transmission between pigs and cattle in herds of mixed production.     

In vitro antimicrobial susceptibility, genetic diversity and prevalence of UDP-glucose 4-epimerase (galE) gene in Campylobacter coli and Campylobacter jejuni from Turkey production facilities

This study evaluated the genetic diversity of multi-drug resistant Campylobacter jejuni (n=44) and C. coli (n=30) isolated from 18 turkey houses. Antimicrobial resistances to ampicillin, ciprofloxacin and nalidixic acid were higher (P<0.05) in C. coli than in C. jejuni strains. PCR analysis indicated that 82% of total isolates tested, including 91% of C. jejuni and 70% of C. coli tested positive for a 496-bp UDP-glucose 4-epimerase (galE) gene. The diversity of isolates was mapped by antibiogram, SmaI-PFGE and flaA-RFLP typing methods using the discriminatory index (DI). RFLP was more suitable in discriminating C. coli (DI=0.895) than PFGE (DI=0.816) or antibiogram profile (DI=0.552), while either PFGE (DI=0.941) or RFLP (DI=0.942) could be used in discriminating C. jejuni strains. The combined PFGE and antibiogram dendrogram had the highest DI for both C. coli (0.910) and C. jejuni (0.968), suggesting that a combination of typing methods is more useful in examining the diverse Campylobacter population on turkey farms.