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11.
Anaplasmoses are common tick-borne zoonotic bacterial diseases of livestock and free-living ungulates from the genus Anaplasma that are recently emerging in Central Europe. The main aim of this study was to analyze the prevalence and genetic variability of Anaplasma phagocytophilum and Anaplasma ovis in small ruminants and questing ticks from six different sites in Slovakia and the Czech Republic using the PCR of the msp4 gene followed by the sequence analysis. At two farms from southeastern Slovakia, 66.1% small ruminants were infected with A. ovis in contrast to one positive animal from both sites in northern Slovakia. It was represented by two different genotypes. A. phagocytophilum was present in all tested flocks with the infection prevalence ranging from 0.9% to 5.7%. None of the tested questing ticks carried A. ovis. A. phagocytophilum was detected in 1.1% and 7.8% of questing Ixodes ricinus ticks collected around the farms located in southeastern and northern Slovakia, respectively. A. phagocytophilum revealed higher intraspecific diversity than A. ovis.  相似文献   
12.
With regard to optimization of the factors of field crop harvest formation in semi-arid areas the phenomenon of soil drought is of key importance. This article deals with the problem of soil water management in connection to soil fertility in the area of East Slovakian Lowland, characterized by the complexity of its agro-ecologic conditions. In clay-loamy soils of the corresponding area, soil water content at the level limited by the threshold point and field water capacity ensures that the average value of actual evapotranspiration intensity varies between 2.69 and 3.89 mm per day−1. Time development of soil water storage and evaporation deficit depends on optimized system of soil water management necessary for plant production.  相似文献   
13.
One main task of forestry is a reliable estimation of the stem form and its development applied in calculating total and log volume. As long as process-oriented models are not available for this practical use, empirical models must serve instead. Taper curve data of trees within stands normally show a rank maintenance,i.e., a tree which has a greater diameter than another one at a certain height, is most probably bigger at any other height, too. This property also applies to the analysed tree species, sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa), and will be well-represented by a linear model formulation. As model parameter sets of single stands have a very limited time validity, two approaches for future stem form prediction are discussed. The one, the centroaffine transformation of a linear taper curve function, is not suitable for representing the time-depending change of the stem form. However, this can be done by a linear unit taper curve model, the parameters of which are based on sample trees of stands of several age classes. Temporary unit parameter sets are derived for sugi and hinoki and the estimated stand volumes are compared to the real ones to evaluate the model performance, which turned out to be very good. We would like to express our gratitude to the Japan Science and Technology Corporation for the financial promotion, which enabled this research work.  相似文献   
14.

Background

A single prolonged milking interval (PMI) e.g. after a technical stop in an automated milking system is of concern for the producer since it is associated with a short-lasting increase in milk somatic cell count (SCC), which is a major quality criterion used at the dairy plants. The content of polymorphonuclear leukocytes (PMN) and how the milk quality is influenced has not been much investigated. The SCC peak occurs without any obvious antigen challenge, possibly indicating a different leukocyte attraction mechanism after a PMI than we see during mastitis.

Methods

Composite cow milk samples were taken at the milkings twice daily during 7 days before and 5 days after a PMI of 24 h. Milk was analyzed for SCC, PMN, fat, protein and lactose, and at some occasions also casein and free fatty acids (FFA).

Results

During the PMI the proportion of milk PMN increased sharply in spite of marginally increased SCC. The peak SCC was not observed until the second milking after the PMI, in the afternoon day 1. However, the peak SCC value in morning milk did not occur until one day later, concomitantly with a decrease in the proportion of PMN. After declining, SCC still remained elevated while PMN proportion was decreased throughout the study as was also the milk yield, after the first accumulation of milk during the PMI. Milk composition was changed the day after the PMI, (increased fat and protein content; decreased lactose, whey protein and FFA content) but the changes in the following days were not consistent except for lactose that remained decreased the rest of the study.

Conclusion

The PMI resulted in increased SCC and proportion of PMN. Additionally, it gave rise to minor alterations in the milk composition in the following milkings but no adverse effect on milk quality was observed. The recruitment of PMN, which was further enhanced the first day after the PMI, appeared to be independent of milk volume or accumulation of milk per se. Hence, we suggest that there is a special immunophysiological/chemoattractant background to the increased migration of leukocytes into the milk compartment observed during and after the PMI.  相似文献   
15.
16.
Salmonella enterica subspecies enterica serovar Choleraesuis is rarely detected in Europe, but the clinical disease has been reported in wild boars. We describe here the clinical findings, pathologic changes, and microbiologic features of swine salmonellosis caused by S. enterica serovar Choleraesuis in weaned piglets in Serbia. In April 2019, on a large farrow-to-finish pig farm, increased mortality was reported in weaned piglets, marked by lethargy, anorexia, pyrexia, and respiratory distress. Gross pathology revealed dermal cyanosis, mesenteric lymphadenopathy, splenomegaly, hepatomegaly, interstitial pneumonia, and colitis. By direct culturing of lung, liver, spleen, and lymph nodes, S. enterica ser. Choleraesuis variant Kunzendorf was isolated after years of absence of the disease in pig farms in Europe. The source of this salmonellosis outbreak caused by S. enterica ser. Choleraesuis remains unknown.  相似文献   
17.
Rapid micropropagation of Nepeta rtanjensis, N. sibirica and N. nervosa was performed. Qualitative and quantitative nepetalactone content in methanol extracts of in vitro grown plants was analysed by reverse-phase HPLC coupled with UV and MS detection. Only trans,cis-nepetalactone was detected in shoots of N. rtanjensis, while cis,trans-nepetalactone stereoisomer was present in N. sibirica. No nepetalactone was observed in shoots of N. nervosa. The antimicrobial activity of methanol extracts, against eight bacterial and eight fungal species, was evaluated. All the tested extracts showed significant antibacterial and strong antifungal activity. However, N. rtanjensis extract exhibited the best antimicrobial potential.  相似文献   
18.
19.

Purpose

A multi-compartment monitoring study was performed to characterize the effect of environmental variables, such as temperature and water flow as well as sediment characteristics, on the distribution and transport of persistent organic pollutants (POPs) in a dynamic river system during 1 year in an industrial region in central Europe.

Materials and methods

Waterborne polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed over a period of 1 year at five sampling sites in the Morava River in the Czech Republic. Contaminants were measured monthly in riverbed sediments, freshly deposited sediments, water samples and passive samplers.

Results and discussion

Sediments are the main carrier of POPs in the river. Distinguishable patterns of PAHs, OCPs and PCBs in sediment indicate that their origin is from distinct sources and different transport pathways. The PAHs were identified as the dominant contaminant group of compounds with a mean concentration in sediment of 5,900 μg kg?1. Such concentrations are up to 10 times higher than in the Danube River, into which Morava drains. In contrast, mean concentrations of PCBs, hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethane and its breakdown products (DDTs) and hexachlorobenzene (HCB) of 6.0, 0.4, 4.2 and 6.0 μg kg1, respectively, are similar to those in the Danube. With some exceptions, no significant difference in composition of surficial riverbed sediments and those collected using sediment traps was observed. Despite the presence of potential local pollutant sources, the differences in contaminant concentrations between sites in the region were in most cases not significant. Variations in POP concentrations in sediments are mainly induced by high flow events, whereas seasonal variability was not observed.

Conclusions

The changes in contaminant concentrations in Morava River sediments are induced by episodic high flow events that cause erosion of contaminant-containing particles and their deposition at suitable downstream sites.  相似文献   
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