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A significant element of the prophylaxis of nosocomial infection in veterinary clinics is monitoring ambient objects, air, equipment, and instruments. In order to determine the role of boxes for keeping ill animals as a source of transmission of pathogens of nosocomial infections in veterinary clinics, we studied the microflora of surfaces of boxes and bioaerosol prior and after sanitation. For this purpose, we collected rinses from the surfaces of plastic and steel boxes, air samples prior to morning sanitation, after cleaning and wiping the surfaces with water and detergents and after disinfection. From the surfaces of the boxes for holding animals, we mostly isolated bacteria of Staphylococcus spp., Streptococcus spp., Micrococcus spp., Corynebacterium spp., Enterococcusspp. and Bacillusspp. Gram-negative species we found were bacteria of Escherichia spp., Acinetobacterspp. and Enterobacterspp. After wet cleaning and disinfection of plastic boxes, we detected species of Staphylococcusspp. and Enterococcusspp. in 5.4% of the samples, Micrococcus spp. in 8.1% and Bacillus spp. in 2.7%. Gram-negative bacteria of Enterobacterspp. were found in 2.7% of the samples. At the same time, the number of microorganisms in samples in which the bacteria were found after disinfection on the surfaces of stainless-steel boxes was 2.0 times lower than in such from the surfaces of plastic boxes. We determined that after wet disinfection of boxes’ surfaces, there occurred decrease in the microbial number in the air, equaling 3.7 times on average, compared with prior to disinfection. The basis of the air microflora after disinfection comprised species of Micrococcusspp., Corynebacterium spp. and Staphylococcusspp., which can be airborne-transmitted. Bacteria that were isolated from the boxes after disinfection (Micrococcusspp., Staphylococcusspp.) formed highly dense biofilms, which probably ensure the survival of the microbial cells, thus making the boxes a probable source of nosocomial infection. [ABSTRACT FROM AUTHOR]

Safety of milk can decline because of high concentrations of steroid hormoneslike 17β-estradiol, which is associated with the development of some oncological diseases and reproductive disorders. We studied the effects of thermal processing of raw milk and technologies of production of butter and yogurt on the concentration of 17β-estradiol. For this purpose, we determined the amount of 17β-estradiol in raw milk, after pasteurization under different regimes, boiling and during the production of butter and yogurt. Content of 17β-estradiol was determined using the method of immunoenzymatic analysis. We determined that low-temperature processing of milk atthe temperature of 77.0 ± 1.0 °С for 1 min caused no changes in the structure of the estrogenic hormone 17β-estradiol, resulting in practically no changes in its amount in pasteurized milk. We determined that 17β-estradiol in milk is a temperature-stable hormone with no tendencies towards significant decrease when subject to high-temperature processing (85.0 ± 1.0 °С for 1 min) and during boiling, because the amount of the hormone decreased on average by 5%. Therefore, we may state that after pasteurization or sterilization, the concentration of 17β-estradiol in drinkable milk would not be significantly different from its initial amount in raw milk. We determined significant increase in 17β-estradiol in butter (3896.1 ± 67.5 pg/g), as compared with the concentration in raw milk (189.4 ± 12.5 pg/mL), and its insignificant content in buttermilk was insignificant (29.3 ± 1.8pg/mL). The concentration of 17β-estradiol in milk decreased by 25% during 9-month storage at the temperature of –18 °С and by 20% at the temperature of –9 °С. This process can be applied to butter made from milk of cows at late stages of lactation, which contains high level of estrogen. We determined that the steroid hormone 17β-estradiol did not break down under the influence of dairy acid that accumulates as a result of lactic acid fermentation, both with the participation of mixed microflora of raw milk and pure lactic-acid bacteria of fermentation starter for yogurt.The prospects of the studies are the development of a safe maximum allowable level of 17β-estradiol in raw milk and methodological evaluation at a milk-processing factory. [ABSTRACT FROM AUTHOR]

Among the acquired mechanisms of resistance to antibiotics of microorganisms, the production of betalactamases, enzymes that inactivate penicillins, cephalosporins, carbapenems, and monobactams, is widespread. Most often, such beta-lactamases, in particular ESBL (extended-spectrum beta-lactamases), are capable of destroying III and IV generations of cephalosporins. One of the important ESBL producers is Escherichia coli and, to a lesser extent, Salmonella enteritidis, which are clinically significant in animals and humans. The purpose of the study was to screen ESBL DDM using cephalosporin markers and screening of mobile extrachromosomal factors of bacterial heredity – plasmids (potentially dangerous factors of genetic transport) in isolates of E. coli and S. enteritidis, polyresistant to aminoderms, from environmental objects, patho- and biological material, raw materials and products of animal origin. Results of our studies have shown the level of their distribution among animals, poultry, since from 13 field isolates of E. coli isolated from the milk of cows with mastitis and pathological material from pigs, ESBL production was found in 3 strains (23.1%) and from 18 field isolates of S. enteritidis isolated from pathological material from poultry, ESBL production was found in 2 strains (11.1%). Based on the results of molecular genetics studies, the presence of resistance plasmids (R-plasmids) in 9 field E. coli isolates was confirmed, 4 of which produced acquired beta-lactamases, incl. ESBL and 8 field isolates of S. enteritidis, 7 of which confirmed the presence of acquired carbapenemases. [ABSTRACT FROM AUTHOR]