Современные методы видовой идентификации термофильных бактерий рода Campylobacter

Abstract

Emergent thermophilic Campylobacter hepaticus is the causative agent of Spotty Liver Disease (SLD) in laying hens. C. hepaticus is difficult to cultivate because commercial media for the isolation and cultivation of Campylobacter contain cefoperazone, which inhibits many isolates of the C. hepaticus species. Campylobacter was isolated using modified Preston broth, incubated at 37 °C under microaerophilic conditions for 7 days and then subcultured onto selective Preston agar, erythritol agar with Oxoid selective additives and 5–7% defibrinated horse blood. Commercial test systems (API Campy) were used for identification. The use of the classical bacteriological diagnostic method, which is considered the 'gold' standard, is limited due to the difficulties of cultivation. The identification of new Campylobacter species requires revision of phenotypic identification algorithms. Specific primers for the identification of new Campylobacter species also need to be developed. In our studies, using the KAM-BAC kit, we detected Campylobacter jejuni DNA in clinically healthy birds. Consequently, the carriage of Campylobacter is massive. 30 samples of test material were examined using the molecular-biological method, and 60 samples using the bacteriological method. Analyzing the results of Campylobacter detection, it should be noted that thermophilic Campylobacteria were isolated from 60 clinical samples by the bacteriological method in 5,0% (3 Campylobacter cultures), and from 30 samples by the molecular-biological method in 27,0% (8 positive samples). Based on the analysis of the study results, it is necessary to conduct an in-depth study of the natural sources of Campylobacter hepaticus distribution, virulence factors, pathogenesis and mechanisms of infections caused by these emergent pathogens. The most promising research in the study of the causative agents of Campylobacteriosis in birds will be based on the application of innovative genomic technologies based on multiplex polymerase chain reactions and genome sequencing of Campylobacter hepaticus.