Comparison of different sampling types across the rearing period in broiler flocks for isolation of Campylobacter spp

A Longitudinal Study on Campylobacter in Conventionally Reared Commercial Broiler Flocks in the United States: Prevalence and Genetic Diversity

Poultry meat contaminated with Campylobacter, a major bacterial cause of foodborne gastroenteritis worldwide, is considered the primary source of human campylobacteriosis. Thus, reduction or elimination of Campylobacter in poultry production will have a significant impact on food safety and public health. Despite the significant progress made over the last decades, many puzzles remain about the epidemiology of Campylobacter on poultry farms, hampering the development of an effective control strategy. This longitudinal study was conducted to determine the prevalence and genetic diversity of Campylobacter in a U.S. commercial broiler production farm system. Cecal contents (15 samples/flock) and boot swabs (3 samples/flock) were collected from approximately 6-wk-old birds from 406 conventional broiler flocks reared in 53 houses on 15 farms (located within a relatively close geographic proximity and managed by the same poultry integrator) for up to eight consecutive production cycles and cultured for Campylobacter. Pulsed-field gel electrophoresis was used to investigate the genetic diversity of the Campylobacter jejuni isolates recovered from the cecal contents. The prevalence of Campylobacter at the farm, house, and flock levels were found to be 93% (14/15), 79% (42/53), and 47% (192/406), respectively. Campylobacter prevalence varied remarkably among different farms and flocks, with some farms or houses testing consistently negative while others being positive all the time over the entire study period. Campylobacter isolation rate changed significantly by sample type (higher by cecal contents vs. boot swabs) and season/production cycle (higher in spring vs. other seasons). The majority (88%; 2364/2675) of the isolates were identified as C. jejuni, and almost all the rest (11%; 303/2675) were Campylobacter coli. Genotyping showed limited diversity within a flock and suggested persistence of some C. jejuni clones over multiple production cycles on the same farm. In conclusion, this study indicated that although Campylobacter prevalence was overall high, there were marked differences in the prevalence among the broiler flocks or farms tested. Future studies aimed at identification of potential risk factors associated with differential Campylobacter status are warranted in order to develop effective on-farm interventions.

Rapid Oxford Nanopore Technologies MinION Sequencing Workflow for Campylobacter jejuni Identification in Broilers on Site—A Proof-of-Concept Study

Campylobacter is recognised as one of the most important foodborne bacteria, with a worldwide health and socioeconomic impact. This bacterium is one of the most important zoonotic players in poultry, where efficient and fast detection methods are required. Current official culture methods for Campylobacter enumeration in poultry usually include >44 h of culture and >72 h for identification, thus requiring at least five working shifts (ISO/TS 10272-2:2017). Here, we have assembled a portable sequencing kit composed of the Bento Lab and the MinION and developed a workflow for on-site farm use that is able to detect and report the presence of Campylobacter from caecal samples in less than five hours from sampling time, as well as the relationship of Campylobacter with other caecal microbes. Beyond that, our workflow may offer a cost-effective and practical method of microbiologically monitoring poultry at the farm. These results would demonstrate the possibility of carrying out rapid on-site screening to monitor the health status of the poultry farm/flock during the production chain.

Research Note: Campylobacter spp. control at field level two years after the implementation of European Regulation (EU) 2017/1495

Campylobacteriosis was the most frequently reported foodborne infection in humans in the European Union in the last years. Campylobacter spp. in broiler flocks from Spain was monitored at farm level during 12-month period (2020–2021). Feces samples were analyzed according to ISO (International Standard Organization) 10272-2:2018. From all samples collected, 54% were Campylobacter spp. positive. Regarding the age, Campylobacter spp. was isolated in 36% of the flocks during thinning and 64% in flocks at slaughter age. In addition, Campylobacter spp. counts increased with the age of the animals. On the other hand, the presence of Campylobacter showed statistical differences between the months of the year (P-value <0.05) in flocks at thinning age that exceeded the ≥1,000 CFU/g limit. The highest rates were found from June to December coinciding with the seasons of summer and autumn. In conclusion, our study shows the situation of Campylobacter spp. in broiler flocks in Spain considering age and season effects. This way, it was found higher rates and counts in broilers close to slaughter age and peaking during the summer to autumn period.

Prevalence, Antimicrobial Resistance, and Molecular Characterization of Campylobacter Isolated from Broilers and Broiler Meat Raised without Antibiotics

Campylobacter is one of the main bacterial pathogens that cause campylobacteriosis in the United States. Poultry is considered a major reservoir for the transmission of Campylobacter to humans. This study aimed to determine the prevalence and molecular characteristics of Campylobacter in the no-antibiotics-ever (NAE) broilers. A total of 414 samples were collected, among which 160 retail chicken samples were purchased from grocery stores and 254 samples were collected from broiler farms located in Mississippi State. The overall prevalence of Campylobacter was 25.4%, and a significantly higher prevalence was observed in retail chicken than in the farm samples (36.3% versus 18.5%; P < 0.0001), respectively. The prevalence of Campylobacter was not different (P = 0.263) between conventional retail (40.0%) and NAE (31.4%) retail chicken. Campylobacter jejuni was the predominant species among the positive isolates, accounting for 78.1%. Among the 82 C. jejuni isolates, 52.4% of the isolates carried the gyrA gene followed by the tet(O) gene (14.6%), whereas toxin-producing genes cdtA, cdtB, and cdtC were carried by 43.9%, 46.3%, and 43.9%, respectively. However, none of these virulence genes were detected in C. jejuni isolated from litter samples. Among tested C. jejuni, 13.6% of the isolates were multidrug resistant. The highest resistance was observed against nalidixic acid (49.2%), followed by tetracycline (23.7%). Our study suggests that the prevalence of Campylobacter was higher in retail meat samples than in environmental samples obtained from farms, and there was no difference in Campylobacter prevalence among conventional and NAE retail chicken. IMPORTANCE The FDA antibiotic withdrawal policy has led to a shift in the production system, from conventional antibiotics fed birds to no antibiotics ever (NAE) raised birds. However, the impact of this shift to NAE on the prevalence and characteristics of Campylobacter has not been studied on the farm or in retail chicken meats. The objective of this study was to determine the current prevalence of Campylobacter and the distribution of their antimicrobial resistance and virulence genes in NAE-raised broilers. The findings of this study will help the industry to take necessary action to develop effective mitigation strategies for reducing Campylobacter contamination in NAE broilers.

Multidrug-Resistant Campylobacer jejuni on Swine Processing at a Slaughterhouse in Eastern Spain

Campylobacteriosis is the most commonly reported gastrointestinal disease in humans in the EU, mainly from poultry meat consumption. C. jejuni is the main species involved in the human disease. However, little is known about the role of swine meat in its epidemiology. Thus, the aim of this study was to assess the epidemiology and antimicrobial resistance of C. jejuni on swine processing at the slaughterhouse. To this end, a total of 21 pig herds were intensively sampled at the slaughterhouse. Campylobacter isolation was based on official method ISO 10272-1:2018, speciation was determined by the hippurate hydrolysis test, and antibiotic susceptibility was performed according to standard disc diffusion assay. The results showed that all batches shed Campylobacter in faeces upon arrival at the slaughterhouse and remained positive at the end of the slaughtering process (42.8%). Moreover, 41.5% of Campylobacter strains isolated were C. jejuni and all of them were resistant to at least one antibiotic, and 96.3% were multidrug-resistant strains. In conclusion, the high level of multidrug-resistant C. jejuni swine batch contamination at the slaughterhouse makes it necessary to include the swine sector in national control programmes to reduce the bacterium and its resistance.

Investigation of Campylobacter colonization in three Australian commercial free-range broiler farms

Campylobacter spp. contaminated poultry products are strongly associated with foodborne illnesses worldwide. Development of effective management strategies to reduce contamination by Campylobacter spp. requires an improved understanding of the numerous factors that drive these contamination processes. Currently, chicken farms are using more free-range chicken meat production systems in response to consumer preferences. However, Campylobacter spp. colonization has rarely been investigated on free-range broiler farms. The present study investigated the temporal and environmental factors influencing Campylobacter spp. colonization of free-range broilers as well as potential sources and genetic diversity of Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) in commercial free-range broiler farms. Genetic linkages among the isolates were analyzed using flaA amplicon analysis. Campylobacter coli was first detected in fecal samples of a commercial free-range broiler flock on day 10 of rearing. Multiple genotypes of C. jejuni and C. coli were identified in this study. The farm environment was identified as a potential source of C. jejuni and C. coli colonization of free-range broilers. The dominant Campylobacter genotype varied between free-range broiler farms over time, with C. jejuni being the most frequently isolated species. These findings enhance the understanding of C. jejuni and C. coli colonization in free-range broiler farms and could inform the development of more effective intervention strategies to help control this important foodborne pathogen.

Genotyping and molecular characterization of antimicrobial resistance in thermophilic Campylobacter isolated from poultry breeders and their progeny in Eastern Spain

Thermophilic Campylobacter spp. are recognized as a major cause of acute bacterial diarrhea in humans, with broiler meat being the most common source of human infection. Antibiotic therapy is usually necessary for severe or prolonged infections, especially in immunocompromised populations such as young or elderly individuals. However, different studies have demonstrated a close association between antibiotic use in animal production and antimicrobial resistance (AMR) in humans. In this sense, there is social pressure to reduce antibiotic administration and find adequate alternatives to control the presence of bacterial infections in farms. However, there is a lack of information related to Campylobacter AMR dynamics through the entire production system from breeders to their progeny. It is unknown if resistance genes are a result of adaptation through chromosomal mutation or through horizontal gene transfer, instead of vertical transmission of DNA from the parent to their progeny. Thus, the main objectives of this study were to assess the main AMR rates present in a poultry production system, to study the relationship between Campylobacter AMR profiles from breeders and their progeny, and to study the presence and distribution of antibiotic resistance genes in poultry production. Regarding AMR rates, ciprofloxacin was classified as extremely high, followed by nalidixic acid and tetracyclines that were classified as very high. Moreover, this study demonstrated a relationship between the AMR patterns and genes found from Campylobacter strains isolated in breeders and those present in their progeny.

Campylobacter prevalence and risk factors associated with exceeding allowable limits in poultry slaughterhouses in Spain

BACKGROUND

Campylobacter is the main pathogen involved in zoonotic gastrointestinal diseases. In 2018, European Regulation 2017/1495 on Campylobacter in broiler carcases came into force. In this context, the aim of the study was to assess the potential risk factors associated with exceeding the 1000 cfu/g (colony-forming units per gram) limit set by the EC in several slaughterhouses in Spain.

METHODS

Data relating to 12 factors were collected using questionnaires. Samples were collected from 12 Spanish abattoirs in June, July and August 2017 (n=1725) and were analysed following the ISO 10272-2:2006 method.

RESULTS

The proportion of Campylobacter-positive samples was 23.7 per cent (n=409). Analysis of flock age (41-50 days) revealed a significantly increased odds ratio (OR) in Campylobacter enumeration (OR=7.41). Moreover, scalding temperature (51.9°C-54°C) was positively associated with an increase in OR (OR=2.75). Time in transit to slaughter for 1-1.5 hours showed a significant decrease in OR (OR=0.25), while time in transit for more than two hours showed an increase in OR (OR=4.44). With regard to carcase weight, a weight of 3.21-3.58 kg showed a decrease in OR (OR=0.01).

CONCLUSION

The outcomes of this study suggest that although most chickens are contaminated by the bacterium, the prevalence of those exceeding the 1000 cfu/g limit is not so high as thought.

Detection of Campylobacter species in different types of samples from dairy farms

BACKGROUND

Livestock, domestic pets and wildlife can be intestinal carriers of thermotolerant Campylobacter species. These reservoirs can in turn contaminate the environment and food products, thus creating pathways to campylobacteriosis in human beings. The purposes of this study were to investigate sampling strategies applied for surveillance of Campylobacter on dairy cattle farms and to identify the presence and species of Campylobacter in different age groups.

METHODS

Boot sock and faecal samples were collected from five dairy herds from three age groups-cows, heifers and calves younger than 12 months-and from milk filters.

RESULTS

Campylobacter species were isolated in 152 of 250 samples, of which 93 isolates were identified as C jejuni, 51 as C hyointestinalis, two as C lari and one as C coli, whereas five isolates could not be identified to species level. Campylobacter species were isolated from 86 of 110 faecal samples, 60 of 97 sock samples and six of 43 milk filter samples.

CONCLUSION

Faecal samples were the optimal sample type for detection of Campylobacter on dairy farms. However, taking multiple types of samples could be recommended in order to optimise the recovery rate and variety of Campylobacter species detected when investigating the presence of Campylobacter on dairy farms.

Wild Bonelli's eagles (Aquila fasciata) as carrier of antimicrobial resistant Salmonella and Campylobacter in Eastern Spain

Wild birds have repeatedly been found to be involved in the dissemination of enteric bacterial pathogens in the environment. The aim of this study was to determine the occurrence of Salmonella and Campylobacter as well as the antimicrobial resistance in wild Bonelli's eagles nestlings in Eastern Spain. In addition, we compared the efficiency of two sampling methods (fresh faecal samples from nest and cloacal swabs from nestlings) for detection of both bacteria. A total of 28 nests with 45 nestlings were analysed. In the nest, Salmonella occurrence was 61 ± 9.2%, while Campylobacter occurrence was 11 ± 5.8% (p < 0.05). In the nestlings, Salmonella occurrence was 36 ± 7.1%, while Campylobacter occurrence was 11 ± 4.7% (p < 0.05). Eight Salmonella serovars were identified, and the most frequently isolated were S. Enteritidis, S. Typhimurium, S. Houston, and S. Cerro. Only one Campylobacter species was identified (C. jejuni). Regarding antimicrobial resistance, the Salmonella strains isolated were found to be most frequently resistant to ampicillin and to tigecycline; however, the sole Campylobacter strain recovered was multidrug resistant. In conclusion, this study demonstrated that wild Bonelli's eagles nestlings are greater carriers of Salmonella than of Campylobacter. Both Salmonella and Campylobacter isolates exhibited antimicrobial resistance. In addition, faecal samples from nests were most reliable for Salmonella detection, while cloacal swab from nestlings were most reliable for Campylobacter detection.

Campylobacter spp. and bacteriophages from broiler chickens: Characterization of antibiotic susceptibility profiles and lytic bacteriophages

Bacteria of the genus Campylobacter are the most common pathogens causing zoonotic diseases in humans. Therefore, the aim of the study was to isolate Campylobacter bacteria from broiler chickens and evaluate their susceptibility to selected antibiotics by determining minimum inhibitory concentrations (MIC), followed by isolation and characterization of bacteriophages specific for Campylobacter spp. The material for the study consisted of field isolates of Campylobacter spp. obtained from the gut (cecum) of broiler chickens directly after slaughter in slaughterhouses, and bacteriophages specific for these strains. We isolated 48 strains from poultry (140 broiler chickens): 31 strains of Campylobacter jejuni and 17 of Campylobacter coli. Identification of the strains was confirmed by multiplex PCR and MALDI-TOF mass spectrometry. Over 83% of Campylobacter strains were resistant to ciprofloxacin, and over half the isolates were resistant to erythromycin, gentamicin, and tetracycline. Resistance to three or more antibiotics was observed in 91.6% of all strains. Four bacteriophages were obtained, and on the basis of their morphological structure, they were assigned to two families of the order Caudovirales: Myoviridae and Siphoviridae. A high percentage of the Campylobacter strains were resistant to at least three of the antibiotic groups tested. All of the phages exhibited lytic activity against the Campylobacter spp. isolates, but the antibacterial effect of the phages was not observed for all strains.

Sources of contamination, prevalence, and antimicrobial resistance of thermophilic Campylobacter isolated from turkeys

AIM

Sources of contamination, prevalence, and antimicrobial susceptibility of thermophilic Campylobacter isolated from turkey samples were determined.

MATERIALS AND METHODS

A total of 300 samples were collected from 3 farms (fecal droppings) and 4 poultry slaughterhouses (neck skins and ceca) located in the middle area of Algeria (Algiers, Boumerdès, and Bouira). After detection, an antibiogram was realized only for slaughterhouses samples.

RESULTS

Samples from cecum (90.0%, 90/100; 95% confidence interval (CI)=84.1-95.9%), fecal dropping (68.0%, 68/100; 95% CI=58.9-77.1%), and neck skin (55.0%, 55/100; 95% CI=45.2-64.8%) were positive for thermophilic Campylobacter (p<0.05). Contamination rate of turkey carcasses was higher in modern slaughterhouse (96.7%) than in traditional slaughterhouses (37.1%) (p<0.05). Isolated strains were resistant to nalidixic acid (NA) (87.5%), tetracycline (TE) (81.3%), ciprofloxacin (CIP) (75.0%), ampicillin (AM) (65.6%), and erythromycin (25.0%) (p<0.05). 96.9% (124/128) of the isolates were multiresistant and 18 drug resistance patterns were registered. The predominant one (43.0%) was AM, NA, CIP, and TE.

CONCLUSIONS

Potential sources of contamination of this fastidious bacterium were noticed in farms and slaughterhouses. Modern slaughterhouse allowed contamination of turkey carcasses more than a traditional slaughterhouse. However, the scalding step could not represent a source of contamination. The most tested strains exhibited resistance to erythromycin and/or CIP. It is worrisome because these molecules are considered as first-choice antibiotics for human campylobacteriosis.

Campylobacter in the Food Chain

Currently Campylobacter is the most commonly reported zoonosis in developed and developing countries. In the European Union, the number of reported confirmed cases of human campylobacteriosis was 246,307 in 2016, which represents 66.3 cases per 100,000 population. The genus Campylobacter includes 31 species with 10 subspecies. Within the genus Campylobacter, C. jejuni subsp. jejuni and C. coli are most frequently associated with human illness. Mainly, the infection is sporadic and self-limiting, although some cases of outbreaks have been also reported and some complications such as Guillain-Barré syndrome might appear sporadically. Although campylobacters are fastidious microaerophilic, unable to multiply outside the host and generally very sensitive, they can adapt and survive in the environment, exhibiting aerotolerance and resistance to starvation. Many mechanisms are involved in this, including pathogenicity, biofilm formation, and antibiotic resistant pathways. This chapter reviews the sources, transmission routes, the mechanisms, and strategies used by Campylobacter to persist in the whole food chain, from farm to fork. Additionally, different strategies are recommended for application along the poultry food chain to avoid the public health risk associated with this pathogen.

Short communication: Absence of campylobacter spp. In intensive rabbit farming in eastern Spain, preliminary results

<p>Campylobacteriosis and salmonellosis are the most frequently reported zoonoses and among the most common causes of diarrhoeal illness in the European Union and the United States, and their incidence appears to be increasing. <em>Campylobacter </em>species are routinely found in poultry, swine, cattle, dairy cows and sheep. So far, there are few descriptions of <em>Campylobacter </em>isolation from rabbits. Rabbit meat is a common item in the Mediterranean diet. In this context, the aim of the present study was to investigate the occurrence of <em>Campylobacter </em>spp. in healthy rabbits reared in intensive farms in the Alto Palancia region, eastern Spain. Caecal contents from 70 healthy does reared on 7 different farms were collected. Bacteriological culture was performed in accordance with ISO 10272-1:2006. All samples tested negative for <em>Campylobacter </em>spp. To our knowledge, this is the first study in which comprehensive monitoring was specifically carried out in order to provide data on the occurrence of thermophilic <em>Campylobacter </em>spp. in large intensive rabbit farms in Spain. However, further microbiological studies throughout the Spanish territory are needed to determine the prevalence and risk of other foodborne pathogens in rabbits at farm level.</p>