Occurrence of Campylobacter spp. in Swedish calves, common sequence types and antibiotic resistance patterns.

AIMS: Cattle are the second most important cause of human campylobacteriosis, after poultry, but there are knowledge gaps regarding Campylobacter in cattle. This study examined the occurrence of Campylobacter, the species present, sequence types and antibiotic resistance in Swedish cattle. METHODS AND RESULTS: Faeces samples collected from 154 calves on seven Swedish farms, and 69 follow-up samples from a second collection occasion, were analysed. Campylobacter were isolated from 77% of calves at the first sampling, with Campylobacter jejuni as the most frequently isolated species. Animals kept on deep straw bedding were less likely to be colonized with Campylobacter. Whole-genome sequencing of 90 C. jejuni samples resulted in 11 sequence types, among which ST-19 and ST-21 were most frequent. Antimicrobial resistance analyses showed that 46% of 142 isolates analysed were resistant to quinolones, while all isolates belonging to ST-19, ST-22 and ST-441 were resistant to ciprofloxacin and nalidixic acid. CONCLUSIONS: Campylobacter jejuni was the species most frequently isolated in calves and a strong association was found between sequence type and antimicrobial resistance pattern. SIGNIFICANCE AND IMPACT OF THE STUDY: The high proportion of calves with quinolone-resistant Campylobacter jejuni should be considered in a One Health perspective.

Detection of Campylobacter spp. in water by dead-end ultrafiltration and application at farm level.

AIMS: The purposes were to evaluate the detection of low levels of Campylobacter in water by dead-end ultrafiltration (DEUF) to determine the sensitivity and suitability for use under field condition. METHODS AND RESULTS: The DEUF technique followed by detection according to ISO 10272 was tested on artificially and naturally contaminated water. Campylobacter were detected in all samples spiked with more than 10 CFU 60 l-1 and in four of nine samples with a concentration below 10 CFU 60 l-1 water. Naturally contaminated water from five different broiler producers was analysed. Campylobacter were detected in four of 12 samples from ponds near the houses and in three of 24 samples from water pipes inside the broiler houses, but not in tap water sampled at the entrance of the broiler houses. CONCLUSIONS: The results indicate that DEUF is useful for detection of low numbers of Campylobacter in large volumes of water. SIGNIFICANCE AND IMPACT OF THE STUDY: Contaminated water is an important source for transmission of Campylobacter to broilers and humans. The concentration of Campylobacter is usually low with a high level of background microbiota. This study shows the advantages of DEUF both in the laboratory and under field conditions.

Ovine footrot: new insights into bacterial colonisation.

Ovine footrot is characterised by interdigital dermatitis (ID) and by the separation of the skin and hoof horn (under-running footrot). Dichelobacter nodosus is the essential pathogen causing footrot; the role of other microorganisms in this disease remains unclear. The aims of this study were (i) to investigate the colonisation of D nodosus, Fusobacterium necrophorum and Treponema species in biopsies from the ovine interdigital skin of healthy, ID and footrot-affected feet and (ii) to characterise the virulence of D nodosus strains in those biopsies. Postslaughter biopsy samples (n=241) were collected and analysed by real-time PCR to determine prevalence and load of the different bacterial species. The highest prevalence and load of D nodosus were found on feet with ID. The vast majority of samples contained virulent D nodosus and some samples contained both virulent and benign D nodosus Notably, the more pathogenic subspecies of F necrophorum was found in samples from UK sheep. Our findings provide further insights into the role bacterial colonisation may play in the early stage of ID and in the progression towards footrot.