Campylobacter jejuni is the leading cause of bacterial food-borne infection; chicken meat is its main source. C. jejuni is considered commensal in chickens based on experimental models unrepresentative of commercial production. Here we show that the paradigm of Campylobacter commensalism in the chicken is flawed. Through experimental infection of four commercial breeds of broiler chickens, we show that breed has a significant effect on C. jejuni infection and the immune response of the animals, although these factors have limited impact on the number of bacteria in chicken ceca. All breeds mounted an innate immune response. In some breeds, this response declined when interleukin-10 was expressed, consistent with regulation of the intestinal inflammatory response, and these birds remained healthy. In another breed, there was a prolonged inflammatory response, evidence of damage to gut mucosa, and diarrhea. We show that bird type has a major impact on infection biology of C. jejuni. In some breeds, infection leads to disease, and the bacterium cannot be considered a harmless commensal. These findings have implications for the welfare of chickens in commercial production where C. jejuni infection is a persistent problem.

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ObjectivesThe use of antimicrobials in food-producing animals has been linked with the emergence of antimicrobial resistance in bacterial populations, with consequences for animal and public health. This study explored the underpinning drivers, motivators and reasoning behind prescribing decisions made by veterinary surgeons working in the UK pig industry.MethodsA qualitative interview study was conducted with 21 veterinary surgeons purposively selected from all UK pig veterinary surgeons. Thematic analysis was used to analyse transcripts.ResultsEnsuring optimum pig health and welfare was described as a driver for antimicrobial use by many veterinary surgeons and was considered a professional and moral obligation. Veterinary surgeons also exhibited a strong sense of social responsibility over the need to ensure that antimicrobial use was responsible. A close relationship between management practices, health and economics was evident, with improvements in management commonly identified as being potential routes to reduce antimicrobial usage; however, these were not always considered economically viable. The relationship with clients was identified as being a source of professional stress for practitioners due to pressure from farmers requesting antimicrobial prescriptions, and concern over poor compliance of antimicrobial administration by some farmers.ConclusionsThe drivers behind prescribing decisions by veterinary surgeons were complex and diverse. A combination of education, improving communication between veterinary surgeons and farmers, and changes in regulations, in farm management and in consumer/retailer demands may all be needed to ensure that antimicrobial prescribing is optimal and to achieve significant reductions in use.

Recent progress in determining the population structure of Campylobacter jejuni, and discerning associations between genotypes and specific niches, has emphasized the shortfall in our understanding of the ecology and epidemiology of this bacterium. We examined the natural structure of the C. jejuni community associated with cattle farmland in the UK by structured spatiotemporal sampling of habitats, including livestock and wild animal faeces, environmental water and soil, over a 10-week period within a 100 km2 area. A total of 172 isolates were characterized using multilocus sequence typing into 65 sequence types (STs). Isolates from cattle faeces were significantly over-represented in the ST-61 complex, whereas isolates from wildlife faeces and water were more likely to belong to the ST-45 complex and a number of unusual STs, many of which were first encountered during this study. Sampling within a narrow spatiotemporal window permitted the application of novel statistical methods exploring the relationship between the genetic relatedness and spatial separation of isolates. This approach showed that isolates from the same sampling squares and squares separated by <1.0 km were genetically more similar than isolates separated by greater distances. Our study demonstrates the potential of multilocus sequence typing combined with spatial modelling in exploring natural transmission pathways for C. jejuni.

HighlightsAntimicrobial agent prescription was monitored in a large UK population of cats and dogs over a 2 year period (2014–2016).Systemic antimicrobial agents were prescribed more frequently to cats; topical prescription was more frequent in dogs.A temporal reduction (2014–2016) in antimicrobial agent prescription was observed in both cats and dogs in this population.Premises which prescribed antimicrobial agents commonly to cats generally also prescribed commonly to dogs.The most frequently prescribed antibiotics were cefovecin in cats and clavulanic acid potentiated amoxicillin in dogs.

Increasing awareness of bacterial antimicrobial resistance in human beings and veterinary medicine has raised concerns over the issue of overprescribing and the indiscriminate use of antimicrobials. Their use in food-producing animals is under scrutiny due to the perceived risk from the zoonotic transfer of resistant pathogens from animals to human beings. This study used focus groups to explore the drivers and motivators behind antimicrobial use and prescribing by veterinary surgeons and farmers in the pig industry in the UK. Studies of two veterinary and four farmer focus groups were undertaken, each with between three and six participants, in three geographically distinct regions of low, moderate and high pig density in England. Thematic analysis of the focus group transcriptions revealed convergent themes, both within and across, the veterinary and farmer focus groups. Veterinary opinion was such that 'external pressures', such as pressure from clients, legislation and public perception, were considered to strongly influence prescribing behaviour, whereas, farmers considered issues surrounding farming systems and management to be greater drivers towards antimicrobial use. Acquiring such in-depth insight into the antimicrobial prescribing behaviours in veterinary medicine provides more detailed understanding of prescribing practice and will aid the development of interventions to promote the responsible use of antimicrobials.

Background: Several studies have shown that a number of serovars of Salmonella enterica may be isolated from wild birds, and it has been suggested that wild birds may play a role in the epidemiology of human and livestock salmonellosis. However, little is known about the relationship between wild bird S. enterica strains and human-and livestock-associated strains in the United Kingdom. Given the zoonotic potential of salmonellosis, the main aim of this study was to investigate the molecular epidemiology of S. enterica infections in wild birds in the north of England and, in particular, to determine if wild bird isolates were similar to those associated with disease in livestock or humans.

Antimicrobial resistance (AMR) has been detected in the microbiota of many wildlife species, including long-distance migrants. Inadequately treated wastes from humans and livestock dosed with antimicrobial drugs are often assumed to be the main sources of AMR to wildlife. While wildlife populations closely associated with human populations are more likely to harbour clinically important AMR related to that found in local humans and livestock, AMR is still common in remote wildlife populations with little direct human influence. Most reports of AMR in wildlife are survey based and/or small scale, so researchers can only speculate on possible sources and sinks of AMR or the impact of wildlife AMR on clinical resistance. This lack of quantitative data on the flow of AMR genes and AMR bacteria across the natural environment could reflect the numerous AMR sources and amplifiers in the populated world. Ecosystems with relatively simple and well-characterized potential inputs of AMR can provide tractable, but realistic, systems for studying AMR in the natural environment. New tools, such as animal tracking technologies and high-throughput sequencing of resistance genes and mobilomes, should be integrated with existing methodologies to understand how wildlife maintains and disperses AMR.