Escherichia coli isolates from various sources from 2018 to 2019 were included in the study. Mcr-1 genes were found in two of 105 animal strains (2%) and seven of 928 human strains (0.8%). All mcr-1-positive strains showed a low level of resistance to colistin (MIC ranged from 4 to 8 µg/ml). Both strains isolated from animals remained sensitive to betalactam antibiotics and did not contain beta-lactamase genes. Beta-lactamases were absent only in one of the strains isolated from humans. Four strains were resistant to cephalosporins with sensitivity to carbapenems and carried class A (blaCTX-M-15 or blaCTX-M-1) or class C (blaCMY-2) extended-spectrum beta-lactamases genes. One strain showed resistance to cephalosporins and meropenem and contained four beta-lactamase genes: blaNDM-1, blaCTX-M-15, blaTEM-1B, and blaCMY-6. Only one strain isolated from animals remained sensitive to ciprofloxacin, the rest showed high level of resistance, had amino acid substitutions in the DNA gyrase genes or mutations leading to overexpression of the mdfA gene. In terms of resistance to aminoglycosides, the strains varied widely and carried up to four aminoglycoside-modifying enzyme genes. One strain isolated from humans showed resistance to tigecycline, but no genes conferring resistance to this antibiotic were found. The data obtained substantiate the need for extended studies on the molecular epidemiology of associated resistance to polymyxins and beta-lactams.
Today, fur farming continues to incur huge losses because of the Aleutian mink disease. Frequently, the pathogen enters the territory of farms together with newly imported mink livestock, which is why the applied immunoelectroosmophoresis reaction has low efficiency if the antibodies have not yet reached a certain level. So for this reason, the problem of accurate and early diagnosis of viral plasmocytosis in newly imported quarantine livestock becomes urgent. The study was carried out using PCR diagnostics of fecal samples from a newly imported population of minks of 30-day age in the fur farm of the North-Western region. Before taking fecal samples, all animals were examined by clinical methods. PCR diagnostics was performed using a set of reagents «Test system "ABN"» according to the manufacturer's instructions. According to the results of the experiment, it was found that out of 40 selected animals without clinical signs of the disease, 29 managed to detect the DNA of the causative agent of viral plasmocytosis. Thus, the use of PCR diagnostics as a method of identifying the Aleutian mink disease virus for newly imported livestock will prevent the development and spread of the disease already at its early stages.
The problem of the spread of bacterial infections of birds associated with opportunistic microorganisms occupies a significant place in the modern infectious pathology of birds.The aim of this work is to determine the species diversity of the dominant etiologically significant bacteria circulating in industrial poultry farming. Based on the results for the period 2019 to 2020, we carried out bacteriological studies of pathological material from birds in poultry farms of various technological directions.The dominant species are Escherichia coli, which accounts for 50.7%, Enterococcus faecalis - 25.4%, and Proteus mirabilis - 8.4%. Also, thermophilic Campylobacter spp. - 4.3% were isolated from the organs, including such epidemiologically dangerous species as Campylobacter jejuni. The microorganisms were virulent and differed in their cultural and biochemical properties.Cultures such as Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Enterococcus faecalis are isolated from many organs, which indicates the generalization of the infectious process, the culture of thermophilic Campylobacter spp. were isolated from the liver, which indicates the organotropy of these types of microorganisms.The species composition of the allocated microflora is determined by the epizootic situation in each individual farm, which results in a different percentage of the dominant species.Pure cultures of thermophilic campylobacter were obtained on selective Preston agar with cultivation for 7 days at a temperature of 42 ° C under microaerophilic conditions. However, culturing Campylobacter hepaticus is difficult because it is sensitive to a number of antimicrobial agents used in Campylobacter enrichment media and selective agar.The emergence of new Campylobacter species requires a revision of phenotypic identification algorithms. MALDI TOF mass spectrometry databases need to be updated and specific primers developed to identify new Campylobacter species.Significant variability of indicators of indication of one or another microflora from the liver and gallbladder indicates significant differences in the etiology of bacterial infections of birds.
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