Multilocus sequence typing of Propionibacterium freudenreichii

Propionibacterium freudenreichii is used as a ripening culture in Swiss cheese manufacture. This study investigates the molecular diversity and the population structure of this bacterium via multilocus sequence typing (MLST). Internal fragments of seven genes sequenced for 113 strains of different subspecies and origins allowed the resolution of 46 sequence types (STs) with occurrence frequencies ranging from 1 to 11. The core genome of the species harbours a low level of nucleotide polymorphism. In our data, single nucleotide polymorphisms account for only 2.28% of the concatenated sequences, and the average polymorphism rate in pairwise comparisons is 0.46%. The analyses reveal quantitatively comparable contributions of recombination and mutation in nucleotide changes at core genome loci along cell lineages. Remarkably, the STs exhibit little if any dairy biotope specialization. Phenotypic characterisation of the strains, based on their aptitude to use lactose and nitrate, shows that the two previously identified subspecies (freudenreichii and shermani) do not reflect the ancestral relationships in the P. freudenreichii population. The considerable phenotypic heterogeneity, found even at the ST level, suggests instead a history of recurrent switches between phenotypes.     

进出口食品中不同血清型沙门氏菌PFGE和 MLST分型比较研究

目的：通过PFGE和MLST两种方法对进出口食品中不同血清型沙门氏菌的分辨力和应用价值进行了比较研究。方法：采用PFGE和MLST两种方法对进出口食品中分离得到的鼠伤寒及肠炎两种血清型共30株沙门氏菌进行分型研究。结果：两种血清型共30株沙门氏菌经PFGE分型可得到23种型别,DI值为0.9563;鼠伤寒和肠炎两种血清型菌分别经PFGE分型,DI值分别为1.000和0.9048。MLST对30株沙门氏菌分型得到4种ST型,DI值为0.5793;鼠伤寒和肠炎两种血清型菌分别经MLST分型,DI值分别为0.2571和0.1333。结论：在分辨力方面,PFGE更适合于同一沙门氏菌血清型的分型,MLST适合于不同沙门氏菌血清型间的分型。MLST在替代、补充血清型分型方面有潜在的优势,PFGE在溯源研究方面似乎更胜一筹。     

Diversity of Salmonella enterica serovar Derby isolated from pig, pork and humans in Germany

Salmonella enterica serovar Derby (S. Derby) is one of the most prevalent serovars in pigs in Europe and in the U.S. and ranks among the 10 most frequently isolated serovars in humans. Therefore, a set of 82 epidemiologically unrelated S. Derby strains isolated between 2006 and 2008 from pigs, pork and humans in Germany was selected and investigated in respect to the transmission of clonal groups of the serovar along the food chain. Various phenotypic and genotypic methods were applied and the pathogenicity and resistance gene repertoire was determined. Phenotypically 72% of the strains were susceptible to all 17 antimicrobials tested while the others were monoresistant to tetracycline or multi-resistant with different resistance profiles. Four major clonal groups were identified based on PFGE, sequence data of the virulence genes sopA, sopB and sopD, VNTR-locus STTR5 and MLST revealing also the new sequence type ST774. Thirty different PFGE profiles were detected resulting in four clusters representing the four groups. The pathogenicity gene repertoire of 32 representative S. Derby strains analyzed by microarray showed six types with differences in the Salmonella pathogenicity islands, pathogenicity genes on smaller islets or prophages and fimbriae coding genes. The pathogenicity gene repertoire of the predominant types PAT DE1 and DE2 were most similar to the ones of S. Paratyphi B (dT+, O5−) and to a minor degree to S. Infantis and S. Virchow PATs. Overall this study showed that in Germany currently one major S. Derby clone is frequently isolated from pigs and humans. Contaminated pork was identified as one vehicle and consequently is a risk for human health. To prevent this serovar from entering the food chain, control measurements should be applied at the farm level.     

Salmonella enterica multilocus sequence typing and its correlation with serotypes

Salmonella enterica is a foodborne pathogen of significant public health concern worldwide. In Thailand, S. enterica has also been ranked among the top five most significant bacterial agents of foodborne illnesses by the Ministry of Public Health. Conventionally, biochemical tests and antigen-antibody agglutination have been used to identify and subtype S. enterica, respectively. The objective of this study was to identify the serotypes of 180 S. enterica isolates. Multilocus sequence typing (MLST) was used to deduce the S. enterica serotypes based on sequence type (ST) correlation as shown in the MLST database (http://mlst.warwick.ac.uk/mlst/). Initially, MLST was used to confirm serotypes of 53 previously identified isolates of S. Enteritidis, S. Typhimurium, S. Hadar, S. Virchow, and S. Infantis isolated in Thailand. MLST and serotype correlation confirmed 52 (of 53) known isolates. MLST was performed in 127 S. enterica isolates of unknown serotypes from various sources. Serotypes of all 127 S. enterica isolates were successfully deduced based on STs. With MLST and PCR-based identification, we have shown that the majority of isolates are of monophasic S. Typhimurium (ST34; 43 isolates) and serotype Rissen (ST469; 37 isolates), in agreement with the top serotypes commonly found in Thailand based on the WHO National Salmonella and Shigella Center. We have also confirmed that MLST is a powerful Salmonella subtyping method which could be used not only as a tracking tool for an outbreak investigation at nucleotide level but also as a serotype predictor for making correlations with food safety regulations.     

Extended MLST-based population genetics and phylogeny of Vibrio parahaemolyticus with high levels of recombination

A collection of 174 global isolates of Vibrio parahaemolyticus were analyzed by multilocus sequence typing (MLST) on the basis of ten conserved genes. The results showed a high level of nucleotide and allelic diversity with the evidence of purifying selection and of frequent recombination. Recombination played a much greater role than mutation in generating genetic heterogeneity. The 174 strains could be assigned into 89 different sequence types, which could be further separated into six clonal complexes (CCs; CC1 to CC6) plus 71 singletons. The three major CCs, namely CC1 to CC3, corresponded to the groups of pre-1996 clinical old-O3:K6 strains (trh⁺, T3SS2β⁺, tdh⁻, T3SS2α⁻, and GS-PCR⁻), post-1996 pandemic strains (trh⁻, T3SS2β⁻, tdh⁺, T3SS2α⁺, and GS-PCR⁺) and non-clinical isolates (trh⁻, T3SS2β⁻, tdh⁻, T3SS2α⁻, and GS-PCR⁻), respectively. The MLST data enable the construction of a phylogenetic structure from the allelic profiles rather the nucleotide sequences, so as to reduce the affect of frequent recombination. The six CCs arose on a background of mutation and recombination, and according to the previously reported data, this bacterium could be evolved fast due to lateral acquisition of foreign genes especially including those encoding virulence determinants. V. parahaemolyticus had a typical epidemic population structure that is driven by mutation, recombination and lateral gene transfer.     

Antimicrobial susceptibility of Salmonella from organic and conventional dairy farms

The objective of this study was to compare antimicrobial susceptibility of Salmonella isolated from conventional and organic dairy farms in the Midwest and Northeast United States. Environmental and fecal samples were collected from organic (n = 26) and conventional (n = 69) farms in Michigan, Minnesota, New York, and Wisconsin every 2 mo from August 2000 to October 2001. Salmonella isolates (n = 1,243) were tested using a broth microdilution method for susceptibility to amoxicillin-clavulanic acid, ampicillin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim-sulfamethoxazole. Herd-level logistic regression and logistic proportional hazards multivariable models were used to examine the association between farm management type and susceptibility to antimicrobial agents. For most antimicrobial agents tested, susceptibility of Salmonella isolates was similar on organic and conventional herds when controlling for herd size and state. Conventional farms were more likely to have at least one Salmonella isolate resistant to streptomycin using logistic regression (odds ratio = 7.5; 95% confidence interval = 1.7-5.4). Conventional farms were more likely to have Salmonella isolates with greater resistance to streptomycin (odds ratio = 5.4; 95% confidence interval = 1.5-19.0) and sulfamethoxazole (odds ratio = 4.2; 95% confidence interval = 1.2-14.1) using logistic proportional hazards models. Although not statistically significant, conventional farms tended to be more likely to have at least one Salmonella isolate resistant to 5 or more antimicrobial agents when compared with organic farms.     

进出口食品中不同血清型沙门氏菌PFGE和MLST分型比较研究

目的通过脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST)两种方法对进出口食品中不同血清型沙门氏菌的分辨力和应用价值进行了比较研究。方法采用PFGE和MLST两种方法对进出口食品中分离得到的鼠伤寒及肠炎两种血清型共30株沙门氏菌进行分型研究。结果两种血清型共30株沙门氏菌经PFGE分型可得到23种型别,DI值为0.9563;鼠伤寒和肠炎两种血清型菌分别经PFGE分型,DI值分别为1.000和0.9048。MLST对30株沙门氏菌分型得到4种ST型,DI值为0.5793;鼠伤寒和肠炎两种血清型菌分别经MLST分型,DI值分别为0.2571和0.1333。结论 在分辨力方面,PFGE更适合于同一沙门氏菌血清型的分型,MLST则适合于不同沙门氏菌血清型间的分型。MLST在替代、补充血清型分型方面有潜在的优势,PFGE在溯源研究方面更胜一筹。     

Salmonella status of pigs at slaughter--bacteriological and serological analysis

Apart from Salmonella monitoring of pig herds during the period of growth to evaluate the efficacy of control programmes, monitoring at harvest level is of relevance to assess the Salmonella status of fattening pigs and the associated risk of introducing Salmonella organisms in the slaughter process. Samples from 1830 fattening pigs were gathered at slaughter. Ileocaecal lymph nodes, rectal and caecal content as well as tonsils were collected for bacteriological examinations, and a part of the diaphragm pillar muscle was taken to gain meat-juice for serological analysis. Salmonella spp. was recovered from 13.8% of all pigs examined. Salmonella Typhimurium and Derby were the dominating serovars. The highest detection rates were found in caecal content followed by ileocaecal lymph nodes. By analysing both organs nearly 90% of all Salmonella positive pigs could be identified. Serological examination revealed 9.6% of the pigs as positive using a cut-off value of OD % ≥ 40. Only one quarter of all Salmonella positive pigs showed also a positive serological result. A reduction of the cut-off value does not necessarily result in a higher compliance between bacteriologically and serologically positive slaughter pigs. Detection of antibodies is useful to verify whether pig herds were previously exposed to Salmonella organisms. However, the Salmonella status of pigs at time of slaughter and the associated risk of dissemination of Salmonella organisms can only be assessed by bacteriological examinations which should include both lymph nodes and caecal content.     

Development of a multilocus variable number of tandem repeat typing method for Oenococcus oeni

Oenococcus oeni is responsible for the malolactic fermentation of wine. Genomic diversity has already been established in this species. In addition, winemakers usually report varying starter culture efficiency. The monitoring of indigenous and selected strains is essential for understanding strain survival and implantation during the winemaking process. In this study, we report the development of the first typing scheme for O. oeni using multiple-locus variable number of tandem repeat analysis (VNTR). The discriminatory power of 14 out of 44 tandem repeat loci in the genome of the PSU-1 strain was initially evaluated with a test collection of 18 genotypically distinct starter strains. Then five VNTR loci, which can be easily scored with the technology used here, were identified and used to genotype a collection of 236 strains, previously classified by restriction endonuclease analysis-pulsed-field gel electrophoresis (REA-PFGE) and multilocus sequence typing (MLST) into 136 REA-PFGE types or 110 MLST types. The discriminatory power of VNTR (as determined by Simpson's index of discrimination) was higher than that of the other two methods, with 201 VNTR types. The targeted VNTR markers were found to be stable and did not change for the clones of the same strain deposited in a collection at intervals of several years. Strains isolated from the different wine producing areas or the products were assigned to phylogenetic groups and were statistically linked with the VNTR profiles. Another interesting observation was that the loci were found in sequences homologous to regions encoding for membrane-anchored proteins.     

High hydrostatic pressure processing reduces Salmonella enterica serovars in diced and whole tomatoes

Fresh and fresh-cut tomatoes have been associated with numerous outbreaks of salmonellosis in recent years. One effective post harvest treatment to reduce Salmonella enterica in tomatoes may be high pressure processing (HPP). The objectives of the study were to determine the potential for HPP to reduce S. enterica serovars Newport, Javiana, Braenderup and Anatum in tryptic soy broth (TSB) and to determine the effect of HPP to reduce the most pressure resistant of the four serovars from fresh diced and whole tomatoes. To evaluate pressure resistance, TSB containing 8 log CFU/ml of one of the four serovars was packaged in sterile stomacher bags and subjected to one of three different pressures (350, 450 or 550 MPa) for 120 s. The most pressure resistant S. enterica serovar evaluated was Braenderup. Subjecting the broth culture to 350, 450 and 550 MPa resulted in a 4.53, 5.74 and 7.09 log reduction in S. Braenderup, respectively. Diced tomatoes (150 g) and whole red round tomatoes (approximately 150 g) were inoculated with 0.1 ml of 9.1 log CFU/ml S. Braenderup, and subjected to the same pressure treatments (350, 450 or 550 MPa). Significant reductions of S. Braenderup concentrations in diced tomatoes (P < 0.05) were seen after processing at 350 (0.46 CFU/g), 450 (1.44 log CFU/g), and 550 MPa (3.67 log CFU/g). In whole tomatoes, significant reductions (P < 0.05) were also seen at 350 (1.41 log CFU/g), 450 (2.25 log CFU/g) and 550 MPa (3.35 log CFU/g). HPP may be an effective post harvest strategy to reduce low levels of S. enterica contamination in whole and diced tomatoes.     

Campylobacter contamination of broiler caeca and carcasses at the slaughterhouse and correlation with Salmonella contamination

In order to estimate the prevalence of Campylobacter spp. and Salmonella spp. on broiler chicken carcasses and the prevalence of Campylobacter spp. in caeca, 58 French slaughterhouses were investigated in 2008. Enumeration of Campylobacter spp. was also performed in order to study the relation between caeca and carcass contamination. A pool of 10 caeca and one carcass were collected from 425 different batches over a 12-month period in 2008. Salmonella was isolated on 32 carcasses leading to a prevalence of 7.5% ([5.0-10.0]_95%CI). The prevalence of Campylobacter was 77.2% ([73.2-81.2]_95%CI) in caeca and 87.5% ([84.4-90.7]_95%CI) on carcasses. No significant correlation was found between Campylobacter and Salmonella. Positive values of Campylobacter were normally distributed and the average level was 8.05 log₁₀ cfu/g ([7.94-8.16]_95%CI) in caeca and 2.39 cfu/g ([2.30-2.48]_95%CI) on carcasses. A positive correlation (r = 0.59) was found between the mean of Campylobacter in caeca and on carcasses (p < 0.001). Thus, carcasses from batches with Campylobacter-positive caeca had significantly (p < 0.001) higher numbers of Campylobacter per gram than batches with negative caeca. These results show that Campylobacter can be present in both matrices and reduction in caeca could be a possible way to reduce the amount of bacteria on carcasses. Of the 2504 identifications performed, 3 species of Campylobacter (Campylobacter jejuni, Campylobacter coli and Campylobacter lari) were identified. The main species recovered were C. jejuni and C. coli, which were isolated in 55.3% and 44.5% of positive samples, respectively. These two species were equally represented in caeca but C. jejuni was the most frequently isolated on carcasses with 57.1% and 42.5% of positive carcasses for C. jejuni and C. coli, respectively. This study underlines that target a reduction of Campylobacter on final products requires a decrease of contamination in caeca.     

Fecal prevalence and diversity of Salmonella species in lactating dairy cattle in four states

Salmonella is one of the most serious foodborne pathogenic bacteria in the United States, causing an estimated 1.3 million human illnesses each year. Dairy cows can be reservoirs of foodborne pathogenic bacteria, including Salmonella spp.; it is estimated that from 27 to 31% of dairy herds across the United States are colonized by Salmonella. The present study was designed to examine the occurrence of Salmonella spp. on dairies and to examine the serotypic diversity of Salmonella isolates on sampled dairies from across the United States. Fecal samples (n = 60 per dairy) were collected from 4 dairies in each of 4 states for a total of 960 fecal samples representing a total population of 13,200 dairy cattle. In the present study, 93 of 960 samples (9.96%) collected were culture-positive for Salmonella enterica. At least one Salmonella fecal-shedding cow was found in 9 of the 16 herds (56%) and the within-herd prevalence varied in our study from 0% in 7 herds to a maximum of 37% in 2 herds, with a mean prevalence among Salmonella-positive herds of 17%. Seventeen different serotypes were isolated, representing 7 different Salmonella serogroups. There were 2 or more different serogroups and serotypes present on 7 of the 9 Salmonella-positive farms. Serotypes Montevideo and Muenster were the most frequent and widespread. From our data, it appears that subclinical colonization with Salmonella enterica is relatively common on dairy farms and is represented by diverse serotypes on US dairy farms.     

Investigation of Salmonella enterica in Sardinian slaughter pigs: prevalence, serotype and genotype characterization

In order to improve the knowledge about the presence of Salmonella in pork meat in Sardinia (Italy), the prevalence and the sources of Salmonella at 5 pig slaughterhouses (slaughtered pigs and environment) were investigated and the isolates were characterised. A total of 462 samples were collected, 425 from pigs at slaughter and 41 from the slaughterhouse environment. Salmonella was isolated from 26/85 (30.5%) mesenteric lymph nodes, 14/85 (16.4%) colon contents, and from 12/85 (14.1%) carcasses and livers. Salmonella prevalence was 38% (8/21) in samples from surfaces not in contact with meat, and 35% (7/20) in those from surfaces in contact with meat. Thirty-one pigs were identified as carriers of Salmonella in lymph nodes and/or colon content, but of these, only 8 carcasses were positive. A total of 103 Salmonella isolates were serotyped and genotyped. Eight different serotypes were detected; the most common were S. Derby (44/103, 42.7%) and S. Typhimurium (24/103, 23.3%). The most prevalent S. Typhimurium phage type was DT193. Thirty-two isolates were found to be resistant to more than one antimicrobial (MDR). Pulse-field gel electrophoresis (PFGE) permitted the resolution of XbaI macrorestriction fragments of the Salmonella strains into 20 distinct pulsotypes. Combined application of a plasmid profiling assay (PPA) and PFGE gave useful additional information to assist in tracing the routes of Salmonella contamination in abattoirs. To reduce Salmonella prevalence some preventive measures should be encouraged: the origin of infected slaughter animals should be identified and direct and cross-contamination of carcasses should be avoided by adhering to HACCP principles in association with good hygiene procedures (GHP).     

Differences in biofilm formation of produce and poultry Salmonella enterica isolates and their persistence on spinach plants

Spinach plants were irrigated biweekly with water containing 2.1 log CFU Salmonella/100 ml water (the maximum Escherichia coli MPN recommended by the Leafy Greens Marketing Agreement; LGMA), or 4.1 CFU Salmonella/100 ml water to determine Salmonella persistence on spinach leaves. Green Fluorescent protein expressing Salmonella were undetectable by most-probable number (MPN) at 24 h and 7 days following each irrigation event. This study indicates that Salmonella are unlikely to persist on spinach leaves when irrigation water is contaminated at a level below the LGMA standards. In a parallel study, persistence of Salmonella isolated from poultry or produce was compared following biweekly irrigation of spinach plants with water containing 6 log CFU Salmonella/100 ml. Produce Salmonella isolates formed greater biofilms on polystyrene, polycarbonate and stainless steel surfaces and persisted at significantly higher numbers on spinach leaves than those Salmonella from poultry origin during 35 days study. Poultry Salmonella isolates were undetectable (<1 log CFU/g) on spinach plants 7 days following each irrigation event when assayed by direct plating. This study indicates that Salmonella persistence on spinach leaves is affected by the source of contamination and the biofilm forming ability of the strain.     

Influence of serotype on the growth kinetics and the ability to form biofilms of Salmonella isolates from poultry

The influence of the serotype on the growth behaviour and the ability to form biofilms of Salmonella enterica strains was investigated. The relationships between biofilm formation and growth kinetic parameters were also determined. A total of 69 strains (61 isolates from poultry and 8 reference strains from culture collections) belonging to 10 serotypes (S. enterica serotype Typhimurium, S. Newport, S. Paratyphi B, S. Poona, S. Derby, S. Infantis, S. Enteritidis, S. Virchow, S. Agona and S. Typhi) were tested. All Salmonella strains produced biofilms on polystyrene micro-well plates (crystal violet assay). Isolates were classified as weak (35 strains), moderate (22), or strong (12) biofilm producers. S. Agona and S. Typhi produced the most substantial (P < 0.001) biofilms. Growth curves were performed at 37 °C in tryptone soy broth by means of optical density (OD_420–580) measurements from 0 to 48 h. Growth kinetic parameters (Gompertz model) varied between serotypes. The maximum growth rate (ΔOD_420–580/h) ranged from 0.030 ± 0.002 (S. Typhi) to 0.114 ± 0.011 (S. Agona). The ability of Salmonella strains to form biofilms was not related to their growth kinetic parameters. The formation of biofilms by Salmonella on polystyrene constitutes an issue of concern because plastic materials are frequently used in food facilities. The findings suggest that special efforts must be made for the effective control of Salmonella in food-processing environments when S. Agona or S. Typhi strains are present.     

Inactivation of Salmonella spp. in liquid whole egg using pulsed electric fields, heat, and additives

This paper evaluates the lethal effectiveness on 7 different Salmonella serovars of the application, in static and continuous conditions, of pulsed electric fields (PEF) followed by heat treatments in liquid whole egg (LWE) with additives (EDTA or triethyl citrate-TC-). Compared to heat treatments, the PEF (25 kV/cm and 75-100 kJ/kg) followed by heat (52°C/3.5', 55°C/2', or 60°C/1') in LWE with 2% TC permitted the reduction of heat treatment time from 92 fold at 52°C to 3.4 fold at 60°C, and 4.8 fold at 52°C in LWE with EDTA for a 9-Log(10) reduction of the population of Salmonella Enteritidis. The new designed treatments inactivated more than 5 Log(10) cycles of Salmonella serovars Dublin, Enteritidis 4300, Enteritidis 4396, Typhimurium, Typhi, Senftenberg, and Virchow, both in static and continuous conditions. Conversely, current heat pasteurization treatments of 60°C/3.5' and 64°C/2.5' reduced 5 Log(10) cycles of various serovars of Salmonella but only 2 and 3-4 Log(10) cycles of Salmonella Senftenberg and Salmonella Enteritidis 4396, respectively. Soluble protein content (SPC) decreased 1.8%, 1.3%, and 5.0% after the successive application of PEF followed by heat at 52, 55, and 60°C in the presence of 2% TC, respectively, whereas 1.6% and 9.4% of SPC were reduced after heat pasteurization at 60 and 64°C, respectively. Results indicate that designed treatments could be an alternative to current heat pasteurization of LWE as showed higher lethal effectiveness against Salmonella serovars with a similar or even lower decrement of the soluble protein content.     

Species diversity and toxigenic potential of Fusarium graminearum complex isolates from maize fields in northwest Argentina

Members of the Fusarium graminearum species complex (Fg complex) are the causal agents of ear rot in maize and Fusarium head blight of wheat and other small grain cereals. The potential of these pathogens to contaminate cereals with trichothecene mycotoxins is a health risk for both humans and animals. A survey of ear rot isolates from maize collected in northwest Argentina recovered 66 isolates belonging to the Fg complex. A multilocus genotyping (MLGT) assay for determination of Fg complex species and trichothecene chemotypes was used to identify 56 of these isolates as F. meridionale and 10 isolates as F. boothii. F. meridionale was fixed for the nivalenol (NIV) chemotype, and all of the F. boothii isolates had the 15-acetyldeoxynivalenol (15ADON) chemotype. The results of genetic diversity analysis based on nine variable number tandem repeat (VNTR) loci supported the hypothesis of genetic isolation between F. meridionale and F. boothii, and provided little evidence of geographic substructure among populations of the dominant pathogen species, F. meridionale. This is the first study to indicate that F. meridionale and F. boothii may play a substantial role in the infection and trichothecene contamination of maize in Argentina. In addition, dominance of the NIV chemotype among Fg complex isolates from Argentina is unprecedented, and of significant concern to food safety and animal production.     

Campylobacter and Salmonella in raw red meats in the United Kingdom: prevalence, characterization and antimicrobial resistance pattern, 2003-2005

The prevalence of Campylobacter and Salmonella was assessed in 3959 raw red meats in the UK during 2003-2005. Meats were more frequently contaminated with Campylobacter (7.2%) than with Salmonella (2.4%). Lamb and other meats (e.g. mutton, rabbit) exhibited the highest contamination from Campylobacter (12.6% and 19.8%, respectively), compared with pork (6.3%) and beef (4.9%). Pork however had the highest contamination from Salmonella (3.9%), followed by lamb (2.0%), other meats (2.0%) and beef (1.3%). Offal samples (36.6%) were more frequently contaminated with Campylobacter or Salmonella than muscle tissue (7.0%). C. jejuni predominated in all meat types. C. coli isolates were more likely to exhibit antimicrobial drug resistance, including quinolones, than C. jejuni. Salmonella typhimurium was the most frequent Salmonella serotype isolated from meats; S. typhimurium DT104/104b isolates exhibited higher rates of multiple drug resistance than other serotypes. The findings reinforce the importance of adequate cooking of meat and good hygiene to avoid cross-contamination.