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31.
Background:  Many causes of mortality in the European brown hare, such as bacterial and viral infections, anticoagulant poisoning, and trauma, may result in hemorrhage. There are, however, no reference values concerning blood clotting in this species.  Objectives:  The aim of this study was to determine reference values for blood coagulation times and related parameters in healthy European brown hares.  Methods:  Blood samples from 30 clinically healthy adult hares (15 males and 15 females) were obtained. Hares were physically restrained for blood collection from the cephalic vein into tubes containing citrate and EDTA.  Results:  Mean ± SD were obtained for thrombin time (TT) (13.97 ± 1.37 seconds), prothrombin time (PT) (13.32 ± 2.15 seconds), activated partial thromboplastin time (APTT) (16.73 ± 1.86 seconds), fibrinogen concentration (2.98 ± 1.06 g/L), and platelet count (355.28 ± 128.73 × 109/L). Conclusions: Reference values for blood coagulation times and other parameters associated with blood clotting will be useful in the laboratory evaluation of hemorrhage in the European brown hare.  相似文献   
32.

Background

Wild rodents are suitable for monitoring environmental pollution and exposure risk assessment for people living in contaminated areas. The content of selected risk elements in the femora of bank vole (Myodes glareolus), yellow-necked mouse (Apodemus flavicollis) and wood mouse (Apodemus sylvaticus) was estimated from the Kolíňany area of Slovakia, which is characterized by a high degree of environmental pollution. The rodents were trapped in February 2011 using standard theriological methods. All animals (n = 32) were adult males in good physical condition. The concentrations of Fe, Cu, Zn and Ni in their bones were determined by atomic absorption spectrophotometry.

Results

The highest concentrations of Fe and Cu were detected in the bones of yellow-necked mouse. Significant differences were observed for the content of Fe between A. flavicollis and M. glareolus (P < 0.05). The highest levels of Zn and Ni were found in the femora of wood mouse; however, significant differences were not detected between the rodents. Moreover, the concentrations of Cu, Zn and Ni were significantly higher in the bones of all three species (P < 0.05) in comparison with the values obtained in the same animal species at the same site in February 2007.

Conclusions

Our results demonstrate an increased accumulation of Cu, Zn and Ni in the femora of M. glareolus, A. flavicollis and A. sylvaticus from the Kolíňany area and thus indicate towards ongoing contamination of this locality.  相似文献   
33.
Few if any methods exist to estimate the effects of stone content (stoniness) on the unsaturated soil hydraulic properties. A relatively simple scaling method is presented to estimate the hydraulic conductivity of unsaturated stony soils having different stone contents. A key assumption of the method is that van Genuchten's water retention parameters α and n of the fine soil fraction are the same as those of the stony soil. The method further assumes a linearly decreasing relationship between the saturated hydraulic conductivity and the stone content, based on previous numerical simulations. Using the proposed method, it is possible to calculate the hydraulic conductivity of unsaturated stony soils, knowing the saturated hydraulic conductivity of the fine soil fraction, the retention curve of the fine soil fraction, and the particular stoniness of the soil.  相似文献   
34.
Two-dimensional gel electrophoresis in combination with mass spectrometry has already been applied successfully to study beer proteome. Due to the abundance of protein Z in beer samples, prefractionation techniques might help to improve beer proteome coverage. Proteins from four lager beers of different origins were separated by two-dimensional electrophoresis (2-DE) followed by tandem mass spectrometric analysis. Initially 52 proteins mostly from Hordeum vulgare (22 proteins) and Saccharomyces species (25 proteins) were identified. Preparative isoelectric focusing by OFFGEL Fractionator was applied prior to 2-DE to improve its resolution power. As a result of this combined approach, a total of 70 beer proteins from Hordeum vulgare (30 proteins), from Saccharomyces species (31 proteins), and from other sources (9 proteins) were identified. Of these, 37 proteins have not been previously reported in beer samples.  相似文献   
35.
Age determination of tropical trees, and monocotyledons in general, is not an easy task. Representatives of the Dracaena genus have survived in woodlands on dry margins of the Tethys tropical forest since the Tertiary Period. Here we present analyses of Dracaena cinnabari (DC) stand dynamics via direct and indirect methods of age determination. The direct method has taken advantage of historical photographs of DC mountain woodlands from Soqotra during an Austrian scientific expedition in 1899 by comparing these with the woodland stage in 2004. A decline in the number of tree individuals is obvious, but considering the little that is known about dynamics of DC woodland, one cannot simply state that such decline means forest destruction. The results from this direct method are compared to an indirect mathematical method of age determination using data from 2003. Indirect age determination values differed only about 6.5% from those obtained with the direct method, indicating that the indirect methodology is quite precise.  相似文献   
36.
Long-term field experiments with annual crop rotation were established in 1955 and 1956 at three locations (Lukavec, ?áslav, Ivanovice) in the Czech Republic, which differ in their climate and soil physicochemical properties. The effect of cattle farmyard manure (FM) and a combination of FM and mineral (NPK) fertilizer application (FMNPK) on nutrient status of soil and the response of winter wheat, and nutrient content of wheat grain and straw were evaluated after ~60 years since the establishment. The results showed higher pseudototal (aqua regia soluble) contents of phosphorus and sulfur from FM and FMNPK application compared with control, whereas the labile and moderatory labile content of individual nutrients (except calcium) varied between treatments. The nutrient content of wheat grain and straw was more significantly (p < 0.05) affected by the location and growing season than by the fertilizers. The substantial changes in wheat nutrient uptake occurred for the weakly acidic loamy Gleyic Phaeozem, whereas the lowest response due to fertilizer application was observed for the acidic Cambisol (sandy loam texture). Even after six decades of FM and FMNPK application, the effectiveness of these treatments was predominantly influenced by the soil and climatic conditions at the individual locations.  相似文献   
37.
Animal by‐products can be recycled and used as sources of essential nutrients. Water‐soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high‐fat diet. Exercise‐trained mice had significantly less perirenal adipose tissue, whereas WSHI‐fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone‐sensitive lipase. WSHI‐fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation‐related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism‐related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high‐fat diet.  相似文献   
38.
European natural mountain Norway spruce (Picea abies) forests are currently subject to extensive disturbances. An improved understanding of the self-regulated regenerative capacity of this forest type is therefore needed. We used the last remnant of natural mountain Norway spruce forests in central northwestern Europe (BNF Brocken natural forest), to analyze (1) the diversity of structure and age distribution of the tree population and (2) the effect of disturbances on self-regulated tree regeneration over the last 264 years. To this end, we combined an assessment of stand structure with dendrochronological investigations and a review of disturbance history. We hypothesized that BNF exhibits a high diversity of tree ages and dimensions and that recruitment and survival of tree regeneration were largely independent from disturbances. BNF showed a high structural and age diversity. Disturbances exhibited no regular temporal pattern. Their effect on tree regeneration was rather complex and changed with observation period. Impeding and facilitating effects of past disturbances on recruitment were significant from 1736 to 1910. From 1911 until 2000, recruitment decoupled from preceding disturbances. Subsequent disturbances facilitated survival of established trees from 1736 to 1820, while afterward no significant influence could be proved. Our study showed that in the course of self-regulated development the tree population of BNF has gradually acquired, or maintained, a diverse structure. Disturbances served as an important driver of diversification. We concluded that increasing deadwood availability and limiting browsing are the key to securing immediate regeneration.  相似文献   
39.
This study shows the effect of organic fertilizers at different stocking rates, on nitrogen (N) leaching, measured using zero-tension lysimeters under undisturbed grassland soil. The experiment included two organic fertilizer types – cow dung with dung water (D) and slurry (S), both at a range of stocking rates: 0.9 LU (livestock unit) ha?1, 1.4 LU ha?1, 2.0 LU ha?1 (corresponding to 54, 84 and 120 kg N ha?1, respectively) and a control (C) treatment. In percolated water, the contents of ammonia nitrogen (NH4+–N) and nitrate nitrogen (NO3?–N) were studied. The average concentration of NH4+–N ranged from 0.91 to 1.44 mg l?1 on fertilized plots compared to 0.55 mg l?1 on the control plot. The average concentration of NO3?–N ranged from 5.2 to 9.5 mg l?1 on fertilized plots compared to 3.2 mg l?1 on the control plot. The results of this study showed that the use of organic fertilizers at chosen stocking rates influenced N leaching, but the concentration of N did not exceed the limits for drinking water permitted by Czech legislation. Stocking rates at 2.0 LU ha?1 and below do not result in elevated N concentrations in percolated water that pose environmental threat.  相似文献   
40.
OBJECTIVE: To assess the impacts of the introduction of foot-and-mouth disease (FMD) and various FMD control programs in southern Thailand. ANIMALS: A native population of 562,910 cattle and 33,088 buffalo as well as 89,294 animals legally transported into southern Thailand. PROCEDURES: A quantitative risk assessment was used to ascertain the probability of FMD introduction, and an intrinsic dynamic model was used to assess impacts. Value for the transmission rate (beta) was estimated. Five scenarios created to assess the impacts of nonstructural protein (NSP) testing, mass vaccination, and culling were examined. Impacts were assessed through an examination of the estimated annual cumulative incidence (ACI) of FMD. The ACIs of various scenarios were compared by use of the Tukey Studentized range technique. RESULTS: beta was estimated at 0.115. Approximately 35,000 cases of FMD would be expected from the baseline situation. A 30% reduction of ACI was detected with the introduction of NSP antibody testing. Prophylactic vaccination resulted in an 85% reduction of ACI. Concurrent use of NSP antibody testing and vaccination reduced the ACI by 96%, and the addition of an eradication policy resulted in a slightly greater decrease in the ACI (98%). CONCLUSIONS AND CLINICAL RELEVANCE: The study used epidemiologic models to investigate FMD control interventions. Results suggested that vaccination has more impact than the use of NSP testing. Use of the NSP test reduced ACI during peak seasons, whereas vaccination diminished the underlying incidence. The best mitigation plan was an integrated and strategic use of multiple control techniques.  相似文献   
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