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In the present study, the presence of flaA, cadF, cdtB, and iam genes of Campylobacter sp. were analysed using PCR. Material for analyses comprised 100 Campylobacter sp. isolates obtained from healthy broiler chickens, fatteners, and calves, among which 84 isolates were ascribed to Campylobacter jejeuni and 16 to Campylobacter coli. All isolates (100%) had the cadF gene responsible for adhesion and the flaA gene determining the motility of the analysed bacteria. The frequency of occurrence of the cdtB gene responsible for the production of the cytolethal distending toxin (CDT) was determined to be high (98.6% in broiler chickens, 75% in fatteners, 62.5% in calves). In case of the iam gene, the highest frequency was recorded in Campylobacter sp. isolated from broiler chickens (84.7%), while in strains collected from fatteners and calves it was lower, amounting to 41.7% and 18.8%, respectively.
The investigations comprised 100 piglets of crossbreed Polish Landrace x Large White Polish breed. Faeces samples were collected on the 2nd d of piglets' life (control). On the 5th d of life of the piglets, probiotic paste was applied and 7 d later, faecal samples were collected again. The material included 100 isolates of Campylobacter sp. obtained from healthy piglets. All isolates were assigned to the Campylobacter coli species. The occurrence of virulence genes was determined by the PCR method. Drug- resistance of the obtained isolates was determined using diffusion tests and E-test strips. All isolates deriving from the control group piglets were found to contain the cαdF gene responsible for adhesion, as well as, gene flaA influencing motility of the examined bacteria. In piglets fed diets supplemented with probiotics, the cαdF gene occurred in 100% isolates and gene flαA - in 99% isolates. Campylobacter coli isolates obtained from piglets from the control group exhibited the highest resistance with respect to ciprofloxacin and enrofloxacin. The similar results were recorded in the case of isolates obtained after the probiotic application. The majority of the isolates generated α type haemolysis (91%-92%). No significant differences were recorded in the capability of generating haemolysis between isolates obtained before probiotic administration and the isolates obtained after the application of the experimental probiotic.
The aim of the study was to present antibacterial properties of bacteria found in sugar beet silage against Shigella. The experiment involved bullocks, from which the pathogenic bacteria were isolated, and microorganisms obtained from silage (without additives). It was found that pathogenic bacteria are inhibited by bacteria present in the silage. Experimental subjects included 10 bullocks (crosses of Limousine with Black and White Lowland (BWL) of 700 kg mean body weight. Silage was prepared from sugar beet leaves contaminated with soil. Plant material was ensiled in 6 PCV containers (barrels) of 200 dm3 in volume closed with a cover allowing the release of gaseous products. The ensiling process lasted 120 days. Samples for chemical and microbiological analyses were collected from three barrel depths (15, 30 and 45 cm) and were subsequently pooled to make a representative sample of 0.9 kg weight. The basic composition of the silage was determined in accordance with AOAC. The strain antagonistic to Shigella was identified by the molecular method: after isolating bacterial DNA, a PCR reaction was performed. The PCR analysis and the DNA sequence analysis showed that the organism which naturally occurs in sugar beet leaf silage and exhibits antagonistic properties to Shigella bacteria was Bacillus subtilis. Shigella spp., a pathogenic microorganism that is of particular concern to humans, was found in the mouth of cattle.
The investigations were conducted on 60 Holstein-Friesian dairy cows (at age 3 year and weight 590 kg) kept in tie-stall barn. The animals were divided into 3 groups of 20 heads each. The control group (K) was fed diets without probiotics, group (EM) – was fed diet with the addition of EM probiotic (dose of 150 ml × t–1 TMR) and group (T) – was fed diet with the addition of ToyoCerin probiotic (dose of 0.2 kg × t–1 TMR). Strains of Escherichia coli were isolated from faeces with the aim to determine their numbers, capability for hemolysis and assessment of their drug-resistance. The isolates were identified as E. coli on the basis of their biochemical properties API 20E (BioMérieux) and the PCR method. When analysing the capability of Escherichia coli for hemolysis, the highest number of haemolytic strains was determined in the faeces of animals fed diets with the addition of the EM probiotic. The examined isolates were characterised by different degrees of resistance to the antibiotics used in experiments. The smallest (P<0.05) number of resistant isolates was determined in group T.
The presented investigations were conducted on a group of 60 porkers of crossbreed Polish Landrace x Large White Polish. The animals were divided into two equal experimental groups. The control group (K) was fed diets without supplementation with probiotics, group (P) - diets with the addition of probiotic (0.2 kg t⁻¹ feed). The aim of the study was to determine the effect of probiotic preparation on total numberof lactic acid rods from the Lactobacillus genus and those forming hydrogen oxide. The second part of experiment concerned the influence of probiotic preparation on the number, haemolytic ability and changes in drug resistance of Escherichia coli isolated from animal faeces. The significantly highest number of Lactobacillus sp. were determined in the saliva of porkers fed diets with the addition of probiotic, while the lowest in the control group. Lactobacillus sp. rods capable of forming hydrogen peroxide were isolated from 17 animals in group K and from three animals in group P. E. coli was determined in each examined sample of faeces. In groups K and P, counts of these bacteria were similar and did not differ statistically. High numbers of haemolytic isolates (haemolysis ß) were found in faeces of animals fed diets with the addition of probiotic. Number and proportions of resistant isolates in groups K and P were different. Gentamicin was characterised by exceptionally high in vitro effectiveness. The used probiotic increased drug resistance of E. coli and increased frequency of incidence of haemolysis ß.
The investigations were conducted on 60 Holstein-Friesian dairy cows (at age 3 year and weight 590 kg) kept in tie-stall barn. The animals were divided into 3 groups of 20 heads each. The control group (K) was fed diets without probiotics, group (EM) -- was fed diet with the addition of EM probiotic (dose of 150 ml ⋅ t-1 TMR) and group (T) -- was fed diet with the addition of ToyoCerin probiotic (dose of 0.2 kg ⋅ t-1 TMR). The volume of 2--10 cm$^3$ saliva was collected from each animal in which the following parameters were determined: number of lactic acid rods from the Lactobacillus genus, number of rods capable of producing hydrogen peroxide. For purpose of precise diagnostics, lactic acid rods were identified on the basis of biochemical traits employing API 50 CHL (BioMérieux), while those manufacturing H2O2 were additionally tested using PCR method. The occurrence of Lactobacillus spp. rods was confirmed in all the examined individuals and in each and every experimental combination. Lactobacillus spp. rods capable of produce hydrogen peroxide were isolated in 17 cows in group K, in 3 individuals in group EM and in 13 animals in group T. EM probiotic strongly significantly restrict the development of Lactobacillus spp. strains are capable to produce hydrogen peroxide.
The investigations involved determining the influence of the way of ensiling of alfalfa on the content of some selected biogenic amines in silages, changes in the content of dry matter, crude protein, lactic and acetic acids as well as of ammonia. The performed microbiological analysis entailed determining total counts and the frequency of occurrence of: Lactobacillus spp. (L. plantarum, L. buchneri, L. brevis), as well as Enterobacteriaceae bacteria mainly responsible for the level of amine concentrations. Experimental silages were prepared from fresh and wilted Lucerne, also using a chemical additive. The highest biogenic amine totals and the highest counts of Lactobacillus spp. and Enterobacteriaceae bacteria were recorded in silages prepared from wilted alfalfa. The applied chemical additive reduced the level of amines in silages and Enterobacteriaceae counts.
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