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This study was conducted to determine the prevalence of Campylobacter spp. isolated from dogs' faecal samples. From June 2012 to June 2013, a total of 210 faecal samples from pet dogs living in different kennels (n = 210) were collected by the owners in Greater Poland Voivodeship, Poznań District, Poland. The study revealed that 105 out of 210 faecal samples (50%) contained Campylobacter. The highest prevalence of Campylobacter spp. occurred in spring (81%), followed by winter (64%). The cadF gene was found in 100% of the isolates tested. The occurrence of the other genes was variable. The isolates from young dogs were characterised by higher occurrence of virulence genes.

We describe the synthesis of nanocomposites, based on nanofibers of silicon carbide, silver nanoparticles, and cellulose. Silver nanoparticle synthesis was achieved with chemical reduction using hydrazine by adding two different surfactants to obtain a nanocomposite with silver nanoparticles of different diameters. Determination of antibacterial activity was based on respiration tests. Enzymatic analysis indicates oxidative stress, and viability testing was conducted using an epifluorescence microscope. Strong bactericidal activity of nanocomposites was found against bacteria Escherichia coli and Bacillus cereus, which were used in the study as typical Gram-negative and Gram-positive bacteria, respectively. It is assumed that reactive oxygen species generation was responsible for the observed antibacterial effect of the investigated materials. Due to the properties of silicon carbide nanofiber, the obtained nanocomposite may have potential use in technology related to water and air purification. Cellulose addition prevented silver nanoparticle release and probably enhanced bacterial adsorption onto aggregates of the nanocomposite material.

In the present study, the presence of flaA, cadF, cdtB, and iam genes of Campylobacter sp. were analysed using PCR. Material for analyses comprised 100 Campylobacter sp. isolates obtained from healthy broiler chickens, fatteners, and calves, among which 84 isolates were ascribed to Campylobacter jejeuni and 16 to Campylobacter coli. All isolates (100%) had the cadF gene responsible for adhesion and the flaA gene determining the motility of the analysed bacteria. The frequency of occurrence of the cdtB gene responsible for the production of the cytolethal distending toxin (CDT) was determined to be high (98.6% in broiler chickens, 75% in fatteners, 62.5% in calves). In case of the iam gene, the highest frequency was recorded in Campylobacter sp. isolated from broiler chickens (84.7%), while in strains collected from fatteners and calves it was lower, amounting to 41.7% and 18.8%, respectively.

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