A decrease in therapeutic effect of some live lacto- and bifdobacteria-based drugs for veterinary use has been observed for the last 20 years that urges scientists to search for new microorganisms possessing probiotic properties. Many studies in this feld are focused onBacillus subtilisthat is widespread in the environment and non-pathogenic for animals and humans. Results of tests ofBacillus subtilisfor its biological properties and antagonistic activity aimed at optimization of methodical approaches for detection of strain with the highest antagonistic effect on some opportunistic microorganisms and their further use as probiotics are described. Cultural morphological and biochemical characteristics of the tested strains conformed to the species characteristics ofBacillus subtilis.Tested strains were nonpathogenic for white mice. Tests showed that spore biomass could be prepared both in liquid and on solid nutrient media. Methodically, spore biomass preparation in liquid nutrient medium is preferable. The tests showed that spores emerged from anabiosis non-uniformly and it depended on original seed spore storage period. Spore cultures stored less than one year emerged from anabiosis more quickly. It was found that the spores formed more readily when the cultures were aerated with oxygen as well as that lag-phase culture medium had a stimulating effect onBacillus subtilisspore germination.Bacillus subtilisstrains were found to have antagonistic effect onEscherichia coli, SalmonellaandStaphylococcus. Area of growth inhibition of the said bacteria was 15–20 mm. TestedBacillus subtilisstrains could be proposed for use as probiotics.

Asynchronous electric drives hold leading positions in the global structure of electricity consumption. That’s why the development and implementation of an energy-efficient asynchronous electric drive are always economically feasible and important. The aim of this article is to develop an algorithm to minimize losses of asynchronous electric drive power. The article offers methods to optimize the level of losses in the winding of an electric motor, powered in a steady-state mode by a frequency converter with a scalar control. The substitution scheme for an asynchronous electric drive is considered as a consistent set of conductivities for the stator and rotor wirings. The research tasks were solved based on theoretical and experimental methods, including mathematical and physical simulation of studied processes using modern measuring and computation devices as well as statistic treatment of experimental data. The article offers methods to minimize the losses of power in the winding of an electric motor, powered in a steady-state mode by a frequency converter with a scalar control. The offered method is significantly different in that it uses the substitution for an asynchronous electric drive expressed as a consistent set of conductivities for the stator and motor wirings and the use of the energy efficiency ratio which determines the losses of power in an asynchronous drive for assessing the efficiency of a drive. The main principle for optimal frequency control of an asynchronous engine in terms of energy efficiency was formulated. The laboratory bench for studying the modes of frequency-controlled electric drives was built. The tested drive AIR100S4 showed an increase in energy efficiency ratio from 0.59 to 0.67.

Статья посвящена изучению устойчивости штамма P. multocida к антибактериальным препаратам. По результату проведенных исследований было выявлено, что микроорганизмы Pasteurella multocida проявляют устойчивость по отношению к следующим антибиотикам: Оптохин, Линкомицин, Бацитрацин. Наибольшие подавляющие воздействие на культуру микроорганизма P. multocida оказывают антибиотики: Цефотаксим, Тилмикозин, Амоксициллин.

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Статья посвящена разработке дифференциально-диагностической среды для идентификации бактерий вида Bordetella petrii. Разработанная селективная среда позволяет выявить бактерии B. petrii в течении 48-72 часов. Разработанные питательные среды специфичны по отношению к бактериям-ассоциантам других видов и родов. Оптимальным составом среды является (на литр): глюконат натрия -20 г, гидролизат казеина-3 г, дрожжевой экстракт-1 г, калий фосфорнокислый однозамещенный -1г, бромтимоловый синий-0,08 г, агар бактериологический-15 г, цефалексин-0,02 г. Показатель чувствительности среды составляет около 100 микробных клеток.