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Upward trend in the number of human yersiniosis cases, caused by bacterium Yersinia enterocolitica, is globally observed nowadays. This microorganism is widely spread in the environment, able to persist for prolonged periods in animal products and propagate under low temperatures. Basic infection sources are meat and meat products. In order to isolate Yersinia enterocolitica from food and feed samples horizontal method for the detection pursuant to GOST ISO 10273-2013 was used. It was noted, that Yersinia enterocolitica isolation is associated with certain difficulties, because the sample contains only small quantities of the agent and only the use of special techniques allows removing the concurrent microflora. It was proposed to use cold enrich­ment (4 ± 1) °C of the test material before conventional technique is started. The technique was validated pursuant to GOST ISO 16140-2011. As a result, it was established that validated method for Yersinia enterocolitica bacteria detection in food products, performed at the Microbiology Laboratory, is specific. The method sensitivity is 10 CFU/cm3. Intralaboratory reproducibility and repeatability were confirmed by relevant tests. Additional culture step at (4 ± 1) °C allows complete inhibition of non-psychrophilic microorganisms’ growth.

The paper presents results of the Salmonella identifcation, testings of recovered isolates for their susceptibility to antibiotics and their serogroup and serovar distribution. In 2012–2017 13,774 tests of animal products were performed, 105 Salmonella contaminated samples were detected which is 0.76% of the total number of the tested samples. As a result, 31 isolates were recovered. It was established that 22 of them belonged to seven serovars: S. enteritidis, S. infantis, S. nigeria, S. montevideo, S. typhimurium, S. derby, S. meleagridis. S. infantis (38.7%) and S. enteritidis (16.1%) were identifed as the most spread serovars. There was observed a trend of increase in contaminated samples: 1.13% in 2012 upto 2.84% in 2017. The performed tests for antimicrobial resistance demonstrated that all isolates were susceptible to the following antibiotics: carbpenemes (meropenem, imipenem), β-lactams (amoxicillin /clavulanate), aminoglycoside (amikacin, gentamycine), macrolides (azithromycin). Most of the isolates demonstrated susceptibility to β-lactam antibiotics (ceftriaxone, cefotaxime), fluoroquinolones (ciprofloxacin) and aminoglycosides (kanamycin). Resistance at least to one antibiotic was detected in 12.9% (4/31) of isolates. Resistance to at least three antibiotics was detected in 6.5% (2/31) of isolates. 58.1% (18/31) of isolates demonstrated multiple resistance (to four or more antibiotics).

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Bacteria of Campylobacter genus are ones of the main zoonotic pathogens causing human and animal diseases. Campylobacter organisms are microaerophiles and, therefore, require low oxygen concentration (3–5%) and high carbon dioxide concentration (3–10%) for their growth. They use amino acids rather than carbons as a source of energy. Classical bacteriological methods for Campylobacter spp. detection are not always successful due to diffi culties in creating optimal conditions for their growth. Therewith, development and implementation of molecular methods for Campylobacter detection and identifi cation are of current importance. Assay for qualitative Campylobacter spp. detection with real-time polymerase chain reaction using CFX-96 thermocycler was optimized. Highly specifi c segment of 16S rRNA gene allowing identifi cation of 6 Campylobacter species: C. jejuni, C. coli, C. lari, C. upsaliensis, C. helveticus и C. hyointestinalis was selected as an amplifi cation target. Optimal magnesium ion concentration (2.5 мМ) and primer annealing temperature (58 °С) were determined. Eighteen reference strains of various bacteria were tested. Only tests of Campylobacter genus strains gave positive results. The method sensitivity was 40 target molecules. The said method was used for testing 76 samples of raw materials of animal origin. Campylobacter spp. genome was detected in 18 samples. Obtained results showed that the optimized variant of real-time polymerase chain reaction based on 16S rRNA gene amplifi cation was a specifi c, sensitive, rapid, reproducible and accurate method for qualitative detection of Campylobacter spp. in samples of raw animal materials.