Performance, gut morphology and microbiology effects of a Bacillus probiotic, avilamycin and their combination in mixed grain broiler diets.

1. This study aimed to determine the effect of avilamycin (AGP) and a multi-strain Bacillus probiotic (DFM) on the performance, gut histology and microbiology of broilers fed on a mixed grain diet. 2. A total of 800 chicks were allocated to four treatments: a control diet, control+AGP, control+DFM, or control+AGP+DFM. Bodyweight, feed intake and FCR were measured at d 0, 21 and 42. Samples were taken at d42 to determine villus height (VH), crypt depth (CD) and ratio (VH:CD). Mucosal E. coli and Lactobacilli counts were measured at d42. 3. At d42, DFM and AGP+DFM significantly increased weight over the control, with AGP returning an intermediate value. FCR followed a similar pattern. DFM and AGP+DFM significantly increased VH and CD in all gut sections compared to the control. 4. DFM and AGP+DFM reduced E. coli counts compared to control, with AGP reducing caecal counts only, while Lactobacilli counts were increased. 5. Divergent histology and microbiology between treatments highlight the different modes of action of AGP and DFM for improving broiler growth and feed efficiency.

[Antibiotic-free poultry production based on innovative nutritional programs with the involvement of probiotics].

EU banned antibiotic growth promoters (AGP) for farm animals and poultry since 2006 in relation to the problem of drug resistance. This requires alternative products for equally efficient prevention and treatment of certain alimentary poultry diseases. One of the most actual trends is the development of innovative nutritional strategies for poultry providing an effective symbiosis between the host and its intestinal microbiota. The study presented was aimed at the comparative evaluation of productivity, nutritive value of meat, and composition of intestinal microbial populations in broiler chicks fed different diets (corn - soybean meal, wheat - sunflower cake, barley - sunflower cake) supplemented with AGP or a probiotic (cellulolytic and lactic microorganisms). In three trials straight-run Cobb 500 broilers reared from 1 to 36 days of age were fed these diets supplemented with bacitracin from 1 to 29 days of age (control) or probiotic preparation from 1 to 36 days of age (70 birds per dietary treatment in each trial). There were no differences in live bodyweight and carcass yield between the treatments in all three trials. In the two trials with sunflower cake, protein content in breast meat was significantly higher by in birds fed probiotic in compare to birds fed AGP (by 10.0 and 6.8%, p<0.05), while fat content in thigh meat was lower by 12.0% (p<0.05) and 14.1% (p<0.01), respectively. Content of amino acids in meat did not differ. Vitamin content in the poultry meat of the experimental groups was significantly higher compared to control (p<0.001). The resulting concentrations of bacitracin in meat in control treatments (no more than 0.02 U/g) did not exceed local legislative limitations. The substitution of the probiotic for AGP beneficially affected the composition of bacterial populations in the duodenum and cecae determined using T-RFLP analysis. It was concluded that the supplementation of diets with probiotic allows to produce antibiotic-free broiler meat without detrimental effects on the productive performance.

Metagenomic bacterial community profiles of chicken embryo gastrointestinal tract by using T-RFLP analysis.

Thirty microbial phylotypes of microorganisms were found in the gastrointestinal tract of chicken belonging to the Hajseks White breed, and 38 phylotypes were found in the gastrointestinal tract of chicken belonging to the Hajseks Brown breed. The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks White breed was dominated by the typical representatives of avian intestinal microflora--bacteria of the family Enterobacteriaceae (47.3%), orders Actinomycetales (13.6%) and Bifidobacteriales (20.6%), and the family Lachnospiraceae (1.1%). The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks Brown breed was dominated by the pathogenic bacteria of the order Rickettsiales (94.8%). The metagenome of gastrointestinal tract of both breeds also contained a small number of genes of unidentified bacteria.

Broiler Cecal Microbiocenoses Depending on Mixed Fodder.

Molecular genetic techniques (NGS sequencing and quantitative PCR) were used to determine the composition of the cecal bacterial community of broiler chickens fed with different mixed fodder. The Cecal microbiome exhibited taxonomic diversity, with both typical inhabitants of avian intestine belonging to the families Clostridiaceae, Eubacteriaceae, and Lactobacillaceae and to the phylum Bacteroidetes, and new un- identified taxa, as well as bacteria of the families Lachnospiraceae and Ruminococcaceae, which were previ- ously considered restricted to the rumen microflora. Contrary to traditional concepts, enterococci and bi- fidobacteria were among the minor components of the community, lactate-fermenting species were absent, and typical avian pathogens of the genus Staphylococcus were detected but seldom. Members of the family Suterellaceae and the genus Gallibacterium, which are responsible for avian respiratory infections, were also detected. Significant fluctuations of abundance and composition of microbial groups within the cecal com- munity and of the parameters of broiler productivity were found to occur depending on the feed allowance. Cellulose content in the feed had the most pronounced effect on the composition aid structure of bacterial communities. Decreased cellulose content resulted in a decrease of bacterial abundance by-aii order of mag- nitude and in increased ratios of members of the phylum Bacteroidetes and the family Clostridiaceae, which possess the enzymes degrading starch polysadcharides. Abundance of the normal inhabitants of avian intes- tine belonging to the genus Ldctobacillus and the order Bacillales decreased, while the share of Escherichia and members of the family Sutterellaceae increased, including some species capable of causing dysbiotic changes in avian intestine. No significant change in abundance of cellulolytics of the families Ruminococca- ceae, Lachnospiraceae, and Eubacteriaceae was observed.

[Myoglobin concentration in blood: a criterion in the evaluation of muscular tissue injury in patients with prolonged crush syndrome]. / Kontsentratsiia mioglobina v syvorotke krovi--kriterii otsenki povrezhdeniia myshechnoi tkani u bol'nykh s sindromom dlitel'nogo sdavleniia.

Blood serum levels of myoglobin, creatinine, urea, beta 2-microglobulin were measured in 37 patients with the prolonged crush syndrome (PCS) injured during the Yerevan earthquake. A drastic increase of myoglobin level in the blood was observed in all the patients by the moment of hospitalization, this level being the higher, the more severe the injury. If PCS complications developed, such as sepsis or acute renal failure, myoglobin level increased by several tens of times. Effective treatment normalized myoglobin level before discharge from hospital.

[The role of carbonyl-amine reaction in biological systems and food technology (review of the literature)]. / Rol' karbonil-aminnoi reaktsii v biologicheskikh sistemakh i tekhnologii pishchevykh proizvodstv (obzor).

Modern ideas about the role of the carbonyl-amine reaction in biochemical systems are reviewed. Some details recently found of the mechanisms of the initial steps of the reactions are considered. The pathways of the formation of numerous by-products are discussed which are very important for taste and aroma of some foodstuffs. Data are presented on nonenzymatic glycosylation of proteins in living organisms, which causes disturbances in their vital functions, diseases and aging. Possible chemical structures of "links" between sugars and protein polypeptide chains, as well as nucleic acids derived from glycosylation are considered. References concerning properties of melanoidins are presented.

[Induction of SOS function in Escherichia coli after exposure to various types of chemical mutagens]. / Induktsiia SOS-funktsii v kletkakh Escherichia coli pri deistvii razlichnykh tipov khimicheskikh mutagenov.

On the basis of the SOS-chromotest which was developed by the authors earlier, the minimum time required for expression of the SOS-response is shown to be 15 min, the maximum being recorded 2 h later. An assay of induction of the SOS-response to the mutagens which act on DNA via various mechanisms (e. g., UV-irradiation, mitomycin C, nalidixic acid, nitroso-methylurea and acridine orange) revealed that all the mutagens under study caused induction of the SOS-response. Analysis of efficiency of SOS induction under the action of a mixture of formaldehyde with various amino acids has shown that arginine, asparagine and, especially, cysteine decrease the level of the SOS-response induction. This fact suggests an opportunity for using the SOS-chromotest not only to identify the mutagens and cancerogens, but also to screen the agents for their antimutagenic activity. The study of the SOS-response in the cells which are deficient in genes for repair and recombination has shown that induction is significantly suppressed in the mutants recA, lexA and recF; it is not modified in sbcB mutants and is significantly increased in the mutant lines recBC, uvrB and, particularly, in the double mutant recBCsbcB.

[Cloning the genetic determinant of alpha-hemolysin and obtaining a series of insertional mutations in this determinant by the transposon Tn1000]. / Klonirovanie geneticheskoi determinanty alpha-gemolizina i poluchenie v nei serii insertsionnykh mutatsii transpozonom Tn1000.

Functionally active genetic determinant of alpha-hemolysin was cloned. Hemolytic plasmid pHly195 was used as a donor of the determinant and pBR322 plasmid served as recipient. Cloning was done with a help of HindIII restriction endonuclease. The recombinant plasmid obtained represents pBR322 plasmid with the built-in fragment of 7.4 kb containing genes of functionally active determinant of alpha-hemolysin. Restriction map was constructed using HindIII, EcoRI, BamHI and SalI restriction endonucleases. Insertional mutagenesis was carried out with the help of the Tn1000 transposon. Plasmid DNAs were isolated from insertional mutants of Hly- phenotype and treated with EcoRI, SalI and BamHI. On the basis of the sizes of restriction fragments of the mutant plasmid DNAs localization and orientation of insertions of Tn1000 into the cloned determinant of alpha-hemolysin were determined.

[Low molecular weight metabolites produced by various Penicillium species]. / Nizkomolekuliarnye metabolity, produtsiruemye nekotorymi vidami Penicillium.

Low-molecular weight volatile metabolites produced by Penicillium farinosum, P. citrinum, P. camemberti and P. chrysogenum were investigated. During first 40 days of cultivation the fungi produced mainly C-8 compounds, and later mainly 2-hexenal was synthesized. Addition of 0.1% linoleic acid significantly stimulated the secretion of volatile metabolites. P. citrinum and P. farenosum produced large quantities of geosmin.

[Nonenzymatic formation of 4,5-dimethyl-3-hydroxy-2(5H)-furanone in foodstuffs]. / Nefermentivnoe obrazovanie 4,5-dimetil-3-oksi-2(5H)-furanona v pishchevykh produktakh.

The mechanism of formation of 4,5-dimethyl-3-hydroxy-2/5H/-furanone in some food-stuffs was investigated. The compound was found to result from condensation of acetaldehyde under oxidative conditions. The intermediate product of the condensation is 2-oxobutanoic acid.

[Nucleic acids of the lymphoid cells of the pregnant rat subjected to space flight and its progeny]. / Nukleinovye kisloty limfoidnykh kletok selezenki beremennykh krys, perenesshikh kosmicheskii polet, i ikh potomstva.

The space flight effect on the synthesis of nucleic acids in spleen lymphocytes in pregnant rats and their offspring was investigated. In addition to the inhibition of the DNA replicative function previously detected in males, activation of RNA synthesis was seen in the pregnant females. Such changes did not develop in the synchronous mockup controls. The 30-day and 100-day old pups of the rats flown in space during the last third of their pregnancy showed no changes in the DNA replicative function. The 100-day old animals displayed only a slight, when compared to the vivarium controls, decline of RNA synthesis which was produced by concomitant factors rather than by microgravity per se. It is supposed that microgravity-induced activation of RNA synthesis in spleen lymphocytes of pregnant rats is associated with the involvement of these cells in adaptive trophic processes that are to maintain plastic homeostasis of the fetus in an unusual environment.

[Isolation and characteristics of compound transposons Tn1000::Tn5]. / Vydelenie i kharakteristika slozhnykh transpozonov Tn1000::Tn5.

Two types of compound transposons were derived. In the first case, transposon Tn5 is inserted into the gene responsible for Tn1000 transposase synthesis. In the other, Tn5 is inserted into the region near the left end of Tn1000, where no functionally significant genes were found. It is known that translocation of the compound transposons does not depend on their size and takes place with the efficiency close to that characteristic of the intact Tn1000. Insertion of Tn5 into the gene coding for Tn1000 transposase results in sharp decrease in the efficiency of Tn1000 translocations. This effect, however, may be eliminated by introduction into the cell of the intact Tn1000.