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Unlabelled: The goal of this work was to provide comparative genetic characterization of the human and animal Brucella melitensis isolates from Mongolia, Russia and Azerbaijan using current molecular-genetic typing methods., Materials and Methods: Twenty eight Mongolian (n = 18), Russian (n = 6), and Azerbaijan (n = 4) human and animal Brucella melitensis isolates were studied using 2 molecular typing methods based on PCR for differential species and biovar specific ORF (open reading frames) molecular targets and MLVA (multiple locus variable number tandem repeats analysis) using primers to 12 known loci., Results: The PCR was used for differential molecular targets (all B. melitensis isolates) were characterized as the B. melitensis biovar 2. The MLVA revealed 7 identical and 5 variable MLVA loci. All the isolates were classified into 25 genotypes using the dendrogram on the data of 12 loci and the cluster related to reference strain B. melitensis 63/9 biovar 2. The B. melitensis isolates having related MLVA genotypes were connected to Mongolian, Russian and Azerbaijan regions. The circulation for two B. melitensis isolates to not typical hosts as camel and yak was demonstrated using molecular typing methods., Conclusion: The genetic characterization of twenty eight B. melitensis isolates from different geographical regions in Mongolia, Russia, and Azerbaijan recognized genetic relationships. On the other hand, the MLVA has high discrimination power with a resulting Hunter and Gaston discriminatory index (HGDI) of 0.9841 revealing genetic diversity for the isolates forming of 25 MLVA genotypes. To improve the system of the brucellosis surveillance in Russia MLVA typing of B. melitensis isolates are necessary to investigate from the Siberian (Republics Tuva, Buryatia, and Irkutsk region) and South (Republics Dagestan, Kalmykia, and Stavropol region) Districts having frontier areas with Mongolia and Azerbaijan.

Experimental evaluation of the biological risks of introducing the genetically modified microorganism (GMM) B. subtilis VKPM B-7092, an active ingredient of the probiotic VETOM 1.1, into an open system was performed. The following features of the GMM were studied: the survival rate of the GMM in bovine gastroenteric tract; its influence on the microbiocenosis; the species composition of microflora of the gastroenteric tract of the animal species; the possibility of transfer of the DNA fragment cloned in the B. subtilis bacterium and containing the gene of human leukocyte alpha2 interferon to the representatives of intestinal microflora of animals fed on the probiotic VETOM 1.1, as well as the GMM transfer to other microorganism species spread in the areas of potential getting of the GMM into the environment (soil). The study revealed no negative effects of the GMM on the animal organism and the environment, including remote aftereffects.

The review of the modern foreign and national publications on a problem of circulation emergent foodborne pathogens in an environment is given; and the most important factors affecting on formation of their ecological niche. The data on frequency of allocation of some bacterial pathogens from animal raw material, water, ground and foodstuff are given. The description of the most investigated trends of occurrence emergent food infections is presented. Possible ways of distribution of new bacterial agents to conditions of anthropogenous transformation of an environment, some features of evolutionary changes of food bacterial pathogens, influencing on their etiological and pathogenetic properties are shown.

After processing the dynamic series of tuberculosis morbidity in the population of the Novosibirsk region by the smooth component methods, two major constituents were defined in morbidity dynamics. In total, they make up about half the total variability of tuberculosis morbidity. The first constituent is due to socioeconomic causes that are common for the whole region. The second one shows rather evident 10-year fluctuations. The same 10-year fluctuations are observed in the dynamics of tuberculosis morbidity among the cattle of the Novosibirsk region by out-stripping that in the population in the northern and eastern areas by 1-3 years.

Comparison of tuberculosis epizootic tension with some parameters characterizing the epidemiological situation in areas with different incidence rates of cattle tuberculosis under present conditions showed their inverse correlation. It is suggested that with a drastic improvement of the epizootic situation, the cattle becomes an agent of natural immunization of inhabitants in poor districts, as evidenced not only by the lack of new cases of tuberculosis in human beings, but by an increase in cases with residual posttuberculous changes in the lung (14.1% of the stock breeders examined in the long poor tuberculosis area versus 3.7% in this infection-free area), as well as by high infection rates (74.2 versus 43.5%).

Influence of bacteriophages of Streptococcus bovis on microbial activity in the rumen was investigated in experiments on cows. Main elements of the mechanism of bacteriophage action on the microflora have been detected. The daily feeding with bacteriophages results in productive infection of sensitive to them rumen bacteria and is associated with increasing bacteriophage concentration in the rumen contents, lower number and activity of amylolytic bacteria, higher cellolytic activity and increased number of bacteria utilizing xylan, cellobiose and xylose. The fermentation is usually shifted to a higher production of propionate and butyrate at the expense of lower acetate. The regulating action of a single bacteriophage feeding on the rumen microflora and its metabolic activity stops on the fifth day. Daily introduction of bacteriophages into the ration of cows under moderate or high levels of feed increases the milk fat by 0.1-0.3%.

In the Komi ASSR, 102.2 thousand mosquitoes, 207 small mammals, 1487 blood serum specimens from people, 793 cow blood sera, 140 blood serum specimens from reindeer were collected in June-August, 1988. Twenty seven virus strains isolated from mosquitoes were classified into Bunyaviridae family according to the data of electron microscopic studies. Identification of the isolates by CFT and IFA showed 18 of the strains to belong to California encephalitis complex and 9 to Bunyamwera complex. Serological studies by neutralization test demonstrates a high frequency of contact of the human population and domestic animals with viruses of the California complex practically in the entire study area: an average of 45% among human subjects, 48% among cattle and 33% among reindeer. Such high values of the immune portions indicate the activity of the discovered natural foci of this complex. The results for Batai virus from the Bunyamwera complex do not indicate its high activity: approximately 2% of positive findings in human subjects and about 4% in the cattle. The results permit a prognosis of California encephalitis and Bunyamwera complex viruses spread in the northern part of Western Siberia.

The results of testing the slaughtered cattle material and environment objects for the presence of Mycobacteria are presented. During 1984-1988 with a stable excretion of pathogenic Mycobacteria, the quantity of the isolated atypical Mycobacteria tended to increase. In 1984 the atypical Mycobacteria made up 24.1% of the cultures isolated from cattle (pathogenic ones being 75.9%); in 1985, 29.0%; in 1986, 31.4%; in 1987, 46.0% and in 1988, 55.8%. For the above period M. bovis amounted to an average of 98.8% with annual fluctuations between 96.65 and 99.1%. During the last 5 years M. tuberculosis cultures ranged from 0.9 to 3.3% (1.92% on the average). M. avium was isolated from cattle in 22 cases out of 212 samples of the examined material (10.3%). As a result of testing of 2397 samples of the environment objects taken from 34 farms, 391 (16.3%) atypical Mycobacteria were isolated. It is necessary to continue, with regard to environmental conditions, the study of animal responses and atypical Mycobacterium carriage in different areas of the country.

A cytopathic rotavirus was isolated from calves with symptoms of diarrhea and underwent 15 passages in bovine embryo kidney cell culture. The specificity of the isolate was confirmed by the neutralization test, immunofluorescence, electron microscopy. The CPE of the isolated in bovine embryo kidney cells was similar to that of the reference strain.

The species composition of methanogenic bacteria taking part in thermophilic and mesophilic methanogenesis of cattle manure was studied. In both cases methanogenic bacteria belonging to the genera Methanosarcina, Methanothrix, and Methanobacterium were identified. The description of Methanosarcina thermophila, Methanosarcina mazei, Methanothrix thermoacetophila and Methanobacterium thermoformicicum are given. The methanogenic bacteria are able to utilize all the methane procursors known to date. In methanetanks fermenting cattle manure acetate-utilizing methanogenic bacteria play the leading role in contrast to the rumen microflora.

A cytomorphological method was used to study the reproduction of bovine adenoviruses: Ad bos 1 - Ad bos 3, belonging to the serological subgroup I, and Ad bos 4, Ad bos 5, Ad bos 7, Ad bos 8, belonging to the serological subgroup II, and those isolated from animal adenoviruses N18 and N3056. Cytomorphological method is supposed to be used not only for revealing bovine adenoviruses but also for determining preliminarily their subgroup belonging.

Biological properties and sensitivity to antibiotics and decametoxin of 464 strains of Ps. aeruginosa isolated at Pedigree Cattle Stations in the Chernovitsy region were studied in vitro. The isolates proved to be resistant to penicillin. Decametoxin, a new antimicrobial drug was at the same level as neomycin by its effect on Ps. aeruginosa (bactericidal concentrations of 62.5 to 125 gamma/ml). Gentamycin prepared in the USSR was approximately 20 times more active against Ps. aeruginosa than decametoxin and neomycin.