Contamination of campylobacter isolates from broilers during slaughtering process

Prevalence and concentration of Salmonella and Campylobacter in the processing environment of small-scale pastured broiler farms

The impact of primary and secondary processing steps on Campylobacter concentrations on chicken carcasses and portions

The change in prevalence of Campylobacter on chicken carcasses during processing: A systematic review

Predominant strains of thermophilic Campylobacter spp. in a german poultry slaughterhouse

Systematic review-meta-analysis of the effect of chilling on Campylobacter spp. during primary processing of broilers

Campylobacter is one of the most important foodborne pathogens worldwide, and poultry is regarded as the main reservoir of Campylobacter. The contamination of Campylobacter in broiler chickens at the farm level is closely related to the transmission of Campylobacter in the poultry production chain. This study identified 464 Campylobacter isolates from 1,534 samples from broiler rearing period and slaughtering process including 233 Campylobacter jejuni isolates and 231 Campylobacter coli isolates. We have observed a dynamic distribution of Campylobacter during broiler chicken production, that 66.3% of Campylobacter isolates were C. jejuni during broiler rearing period, while C. coli occupied 60.4% of Campylobacter isolates during the broiler slaughtering process. A tag-label method allowed us to track the dynamic of Campylobacter in each broiler chicken from 31-day age at rearing to the partition step in the slaughterhouse. At the 31-day during rearing, 150 broiler chicken were labeled, and was tracked for Campylobacter positive from rearing period to slaughtering process. Among the labeled broiler, 11 of the tracking broiler samples were able to detect Campylobacter from rearing period to slaughtering. All Campylobacter isolates from the 11 tracking samples were sequenced and analyzed. C. jejuni isolates were divided into four STs and C. coli isolates were divided into six STs. Isolates with identical core genome were observed from the same tag-labeled samples at different stages indicating a vertical transmission of Campylobacter in the early broiler meat production. Meanwhile, the core genome analysis elucidated the cross-contamination of Campylobacter during the rearing period and the slaughtering process. The virulotyping analysis revealed that all C. jejuni isolates shared the same virulotypes, while C. coli isolates were divided into three different virulotypes. The antimicrobial resistance gene analysis demonstrated that all Campylobacter isolates contained at least two antibiotic resistance genes (ARGs), and the ARG profiles were well-corresponding to each ST type. Our study observed a high prevalence of Campylobacter during the early chicken meat production, and further studies will be needed to investigate the diversity and transmission of Campylobacter in the poultry production chain.

A randomized controlled trial (RCT) was carried to evaluate the effect of a feed additive on Campylobacter contamination of broilers reared in commercial conditions. Twenty-four broiler flocks naturally contaminated with Campylobacter were enrolled in the RCT: 12 were assigned to a control group (C) fed with a conventional finishing feed from 4weeks of age to slaughter (around 35days), and the other group of 12 flocks (S) was fed with a finishing feed supplemented with 250ppm of a patented feed additive (an ion-exchanged clay compound) previously proven to reduce Campylobacter contamination in broiler caeca under experimental conditions. Enumeration of Campylobacter colonies in caeca (8 per flock) was carried out following ISO standards before feed distribution and at slaughter. Before treatment, the caecal Campylobacter load tended to be lower in C flocks (7.1±1.9 log CFU/g, CI95% [6.6-7.5]) than in S flocks (7.7±1.0 log UFC/g, CI95% [7.5-7.9]) (p=.05). At slaughter, the bacterial load was similar in the S (7.7±1.0 log CFU/g, CI95% [7.5-7.9]) and C groups (7.5±1.2 log CFU/g, CI95% [7.2-7.8]) (p=.73). Therefore, the feed additive had no significant effect on the caecal Campylobacter load at slaughter under the tested conditions. The logistical constraints inherent in field trials and the natural variability of Campylobacter contamination in naturally infected broiler flocks make it difficult to reproduce experimental results in in situ farm conditions. RCT testing of an intervention strategy in commercial situation is therefore a key step in evaluating pre-harvest interventions against food-borne pathogens.

Prevalence, strain identification and antimicrobial resistance of Campylobacter spp. isolated from slaughtered pig carcasses in Brazil

The European Food Safety Authority (EFSA) has estimated that a proportion ranging from 20% to 30% of campylobacteriosis in humans may be attributed to the consumption of broiler meat and a reduction in the numbers of Campylobacter in the intestines of infected birds at slaughter by 3 log units would reduce the public health risk by at least 90%. In this study, a stochastic model was implemented to reproduce the dynamics of Campylobacter transmission in broiler flocks and explore the effects of several management conditions and/or on-farm mitigation strategies on the estimated level of contamination of infected flocks at slaughter. Results were expressed as ‘proportion of highly contaminated flocks’ (%HCFs) and estimated as a function of the proportion of infected birds in the flock the day of final depopulation and the individual level of contamination in infected birds. The effects of the mitigation strategies aimed at reducing the level of contamination in infected birds were modelled assuming that those effects are exerted on the distribution describing the bacterial load in infected birds. The impact of management conditions such as the adoption of enhanced biosecurity measures (B+) and/or partial depopulation during the production cycle (T+) were quantified using results of an extensive epidemiological study conducted in UK. A standard broiler flock was reproduced and used as baseline to make comparisons and simulate the effects of the mitigation strategies of interest. The baseline model predicted 18.8% probability of HCFs at slaughter. A positive effect ranging from −32.44% to −4.78% was attributed to B+ while T+ had negative effect ranging from +17.55% to +86.70%. When both the effects were tested simultaneously (B+T+), results were not conclusive with %HCFs ranging from −20.21% to +77.65%. When mitigation strategies operating on Campylobacter concentration in intestine were tested, a reduction of 100% and 99.6% in %HFCs were estimated following a generic treatment with bacteriocins and bacteriophages. Reduction in %HCFs as a function of immunization measures were explored and a reduction of 15% in the rate of transmission led to a %HCFs at slaughter reduced by almost 50%. The model was developed to be flexible, easily reproducible, updatable and adaptable to several baseline scenarios. The main parameters and assumptions underlying the baseline model were tested and a sensitivity analysis was performed to identify and discuss the impact that the uncertainty in the baseline information might have on the outcomes.

Method to Rapidly Enumerate Salmonella on Chicken Carcasses

Campylobacter infection is the leading foodborne bacterial gastroenteritis worldwide and the bacteria are frequently isolated from the intestines of chickens. The broiler meat contamination with C. jejuni or C. coli may occur during slaughter processing. The aim of the study was to investigate the prevalence of Campylobacter in poultry flocks and the corresponding broiler carcasses in 15 districts (voivodeships) all over Poland. A total of 128 samples from broiler flocks and the corresponding carcasses were collected between February 2011 and April 2013. The Campylobacter isolation and species identification were performed according to ISO 10272-1 standard and with PCR. It was found that 112 flock (96.5%) were contaminated with campylobacters, either C. jejuni (77 samples; 68.7%) or C. coli (35 flocks; 31.3%). Analysis of the corresponding chicken carcasses tested after chilling revealed that 77 out of 128 (60.2%) samples were positive for Campylobacter, either C. jejuni (58; 75.3%) or C. coli (19; 24.7%). Most of the carcasses were contaminated with the same Campylobacter species as identified in the corresponding flock before slaughter. As tested by PCR, out of the 77 crops with C. jejuni 58 were positive for the same bacterial species. On the other hand, out of the remaining 35 flocks infected with C. coli, only 19 corresponding carcass samples were contaminated with C. coli. In three cases in the slaughtered flocks C. jejuni was identified but in the same carcasses C. coli was found. The opposite findings (flock positive for C. coli but the corresponding carcasses contaminated with C. jejuni) were seen in six voivodeships. It was also observed that several carcass samples were negative for C. jejuni and C. coli although the original flocks were Campylobacter-positive before slaughter (total 36 of the 77 samples; 46.7%). On the other hand, some carcasses were contaminated with Campylobacter although the flocks were negative for these bacteria (9 samples; 11.7%) which may also be due to internal contamination during slaughter of broilers.

Salmonella is one of the most common foodborne pathogens worldwide. Salmonella infections in humans are mainly associated with consumption of poultry products contaminated with this foodborne pathogen. Therefore, strict sanitary measures are necessary to control Salmonella contamination during the slaughtering process of poultry. The objective of this study was to determine the occurrence and transmission of Salmonella at a series of steps in the slaughtering process of chicken. A total of 601 samples were collected from a series of slaughtering steps (10 sampling sites) of 26 chicken slaughterhouses throughout Korea. Salmonella was isolated from samples and its distribution was analyzed along the slaughtering process. Isolates from each sampling site were tested for susceptibility to 15 antibiotics by the broth microdilution method. They were also genotypically characterized by pulsed-field gel electrophoresis (PFGE). Salmonela was isolated from 168 out of 601 samples. Sixteen serotypes were identified while six isolates were untypable. Salmonella enterica serovars Montevideo (n = 29) and Virchow (n = 27) were the most common serotypes out of 119 nonredundant isolates. Relatively high contamination rates of Salmonella were found in shackles (75.0%), feathers near plucking machine (68.5%), and feces from crates (44.0%). Twenty-three antibiotic resistance patterns were recognized and 40 (33.6%) isolates were resistant to five or more antibiotics. The same serotypes of Salmonella were distributed along the slaughtering process of each Salmonella-positive slaughterhouse. Most of those isolates belonging to the same serotype had identical or closely related PFGE profiles. They also shared common antibiotic resistance patterns. Overall findings of this study indicated that Salmonella were sequentially transmitted through the chicken slaughtering process. PRACTICAL APPLICATION: This study provides useful information on the distribution and transmission of Salmonella serotypes through the chicken slaughtering process. Overall findings indicated the need for routine microbiological monitoring along the slaughtering process. This study also showed that on-farm control of Salmonella is needed to obtain Salmonella-free chicken carcasses.

Campylobacter jejuni is one of the most bacteria that cause food-borne diseases worldwide. Campylobacteriosis is commonly associated with the consumption of poultry meat; however, several outbreaks of the disease have also been linked to the ingestion of milk, usually due to failures in the pasteurization or even by raw milk’s consumption. This study aimed to evaluate the occurrence of C. jejuni in samples of raw or pasteurized milk, as well as evaluate different methodologies for analysis of this microorganism. Thirty milk samples were analyzed, 15 samples of raw milk and 15 samples of pasteurized milk, acquired in the metropolitan region of Curitiba, state of Paraná, Brazil, between September 2012 and March 2013. The samples were subjected to counting of C. jejuni by direct plating and to the research after selective enrichment. None of the pasteurized milk samples showed C. jejuni contamination through both evaluated methods. By the direct plating method, were identified the contamination in two samples of raw milk, which presented counts of 4,0 x 101 and 1,65 x 102 CFU/mL. By using the selective enrichment method, C. jejuni was detected in four samples of raw milk, indicating the higher efficiency of the qualitative method in recovering injured cells and thus the higher reliability for detection of this pathogen. The occurrence of milk contaminated by C. jejuni should serve as a warning to guide preventive measures for the control and elimination of this pathogen in the production and manufacturing chain of the product.

Campylobacter jejuni and Salmonella typhimurium are the leading causes of bacterial food contamination in chicken carcasses. Contamination is particularly associated with the slaughtering process. The present study isolated C. jejuni and S. typhimurim from fifty chicken carcass samples, all of which were acquired from different companies in Riyadh, Saudi Arabia. The identification of C. jejuni was performed phenotypically by using a hippurate test and genetically using a polymerase chain reaction with primers for 16S rRNA and hippurate hydrolase (hipO gene). For the dentification of S. typhimurim, a serological Widal test was carried out using serum anti-S. typhimurium antibodies. Strains were genetically detected using invA gene primers. The positive isolates for C. jejuni showed a specific molecular size of 1448 bp for 16S rRNA and 1148 bp for hipO genes. However, the positive isolates of the invA gene exhibited a specific molecular size at 244 bp using polymerase chain reaction (PCR). Comparing sequencing was performed with respect to the invA gene and the BLAST nucleotide isolates that were identified as Salmonella enterica subsp. enterica serovar typhimurium strain ST45, thereby producing a similarity of 100%. The testing identified C. jejuni for hippuricase, GenBank: Z36940.1. While many isolates of Salmonella spp. that contained the invA gene were not necessarily identified as S. typhimurim, the limiting factor for the Widal test used antiS. typhimurum antibodies. The multidrug resistance (MDR) of C. jejuni isolates in chickens was compared with the standard C. jejuni strain ATCC 22931. Similarly, S. typhimurium isolates were compared with the standard S. typhimurium strain ATCC 14028.

The study introduces a new approach for a qualitative transmission assessment of MRSA throughout the pig slaughter process. Based on prevalence data found in literature the MRSA contamination and elimination rates of each individual slaughter step were estimated. The rates were used to set up a Monte Carlo simulation for modeling the propagation of MRSA along the process chain and to quantify the impact of a variable initial prevalence on the outcome prevalence of the carcasses. Sensitivity analyses for the model as well as three different scenarios were performed to estimate the impact of cross contamination during slaughter and to determine the process stages where hygiene interventions are most effective.Regardless of the initial extent of MRSA contamination low outcome prevalences ranging between 0.15 and 1.15% were achieved among pig carcasses indicating that the pig slaughter chain generally includes process steps with the capacity to limit carcass contamination. Especially scalding and singeing can lead to a significant reduction of superficial MRSA contamination during the first half of the slaughter process. Nevertheless, scenario analyses showed that the low MRSA outcome prevalence can only be guaranteed if recontamination during the ongoing slaughter process is obviated. In order to ensure a low MRSA load on pig carcasses at the end of slaughter the abattoir should primarily concentrate on controlling the process parameters of scalding and singeing and avoiding recontamination at subsequent process steps.