Water cycle investigations in Hungarian forest ecosystems

From the biological point of view the value of autotrophy plant association is determined by the carbon fixation and the carbon cycle. Among the plant associations of Hungary, forest has the largest biological carbon fixation and carbon cycle.In general, the annual water cycle is the key factor in the organic material production of the Hungarian forests. The most intensive water consumption and organic material production take place from May till July, which period is named main water consumption and respectively main growing period. In Hungary the categories of the forest climate are characterized by main tree species and based on the characteristic meteorological data (Jaro and Tatraaljai, 1985). In Hungary the forest area covered by stand is 1,650,000 hm2. Beech forest climate covers 8% of the forest area, hornbeam-oak forest climate covers 22%, sessile oak-Turkey oak forest climate covers 48% and forest steppe climate covers 22%. Partly in the frame of ICP-Forests, the Department of Ecology in the Forest Research Institute carries out long term, complex ecophysiological investigations on several sample plots (so-called basic plots) throughout the whole country. The organic material production (growth), the nutrient and water cycle, the measurements of air pollutants and meteorological parameters, as well as chemical analyses are all part of the investigations. As a comparison the figure of two basic plots (Sopron-Piispokladany) shows the water cycles of a good growing beech stand in beech climate and a weak pedunculate oak stand in forest steppe climate in the hydrological year of 2001-2002. In the Hungarian forest 60%-70% of the precipitation is used for interception, evaporation, and in the vegetation season, for the transpiration both in beech and forest steppe climate. From other point of view, only 30%-40% of the open air precipitation infiltrates into the soil and can be utilized by the forest.     

Effects of ochratoxin A on some production traits, lipid peroxide and glutathione redox status of weaned piglets

The effect of feeding ochratoxin A (OTA) contaminated diet (379.6 and 338.1 microg/kg in starter and grower diets) on production traits, lipid peroxidation and some parameters of the glutathione redox system were investigated in weaned piglets over a seven-week period. Feed intake and feed conversion ratio (FCR) did not differ significantly, but in the first phase (0-28 days) the daily weight gain was significantly lower in the piglets fed the OTA-contaminated diet. Lipid peroxidation, as measured by the amount of malondialdehyde, glutathione content and glutathione peroxidase activity, did not change significantly in the blood plasma and red blood cell haemolysate in the OTA-loaded group, while malondialdehyde content increased significantly in the liver and markedly but not significantly in the kidney of piglets fed OTA-contaminated feed. Glutathione content did not differ significantly in the studied organs of the two groups while glutathione peroxidase activity of the OTA-loaded animals was significantly lower both in the liver and in the kidney. The results suggest that the use of feed-stuffs contaminated with low levels of OTA for seven weeks did not cause marked differences in the production traits or in lipid peroxidation and amount or activity of the glutathione redox system in the blood plasma, red blood cells and kidney, while significant changes occurred in the liver homogenate.     

Economic and management value of weed maps at harvest in semi-arid cropping systems of the US Pacific Northwest

Precision Agriculture - Weed maps created late in the growing season are potentially useful in regions where late maturing weeds are problematic and need to be controlled before they produce seed....     

Validation of a disease model in Japanese quail (Coturnix coturnix japonica) with the use of Escherichia coli serogroup O2 isolated from a turkey

This study established a disease model and protocol for bacterial challenge with Escherichia coli serogroup O2 strain EC317 in Japanese quail. Five groups of 10 birds each were injected subcutaneously in the breast with 200 μL of a brain-heart infusion (BHI) culture containing 1 × 10(8), 1 × 10(7), 1 × 10(6), 1 × 10(5), or 1 × 10(4) colony-forming units/mL of the test organism, which had been isolated from a turkey with cellulitis and septicemia. Birds in a 6th group were controls that received sterile BHI alone. Localized lesions of cellulitis developed in all of the birds that received E. coli. The morbidity and mortality rates were highest (100%) in the birds receiving the highest dose of E. coli and decreased linearly with decreasing dose (P < 0.05). Severity of disease, including lesions of pericarditis and perihepatitis, was also directly proportional to the dose of E. coli. These findings indicate that this disease challenge protocol can be used to study disease resistance and immunologic consequences of contaminant exposure or other stressors in birds.     

Expression of claudin-5 in canine pancreatic acinar cell carcinoma - An immunohistochemical study

Claudin-5 is an endothelium-specific tight junction protein. The aim of the present study was to detect the expression pattern of this molecule in intact pancreatic tissues and in well-differentiated and poorly differentiated pancreatic acinar cell carcinomas from dogs by the use of cross-reactive humanised anticlaudin-5 antibody. The necropsy samples taken from dogs included 10 nonneoplastic pancreatic tissues, 10 well-differentiated pancreatic acinar cell carcinomas, 10 poorly differentiated pancreatic acinar cell carcinomas, 5 intrahepatic metastases of well-differentiated and 5 intrahepatic metastases of poorly differentiated acinar cell carcinomas. A strong lateral membrane claudin-5 positivity was detected in exocrine cells in all intact pancreas samples. The endocrine cells of the islets of Langerhans and the epithelial cells of the ducts were negative for claudin-5. The endothelial cells of vessels and lymphatic channels in the stroma of the intact pancreas showed strong membrane positivity for this claudin. All well-differentiated exocrine pancreas carcinomas and all poorly-differentiated pancreatic acinar cell carcinoma samples showed a diffuse loss of claudin-5 expression. The claudin-5-positive peritumoural vessels and lymphatic channels facilitated the detection of vascular invasion of the claudin-5-negative cancer cells. In liver metastasis samples, the pancreatic carcinomas were negative for claudin-5. It seems that the loss of expression of claudin-5 may lead to carcinogenesis in canine exocrine pancreatic cells.     

Amount and chemical element content of rhizomorphs in the stemflow and throughfall areas of beech stands on different soil types

Rhizomorphs of Armitlaria mellea Karst s.l. were collected in the stemflow and throughfall areas of beech stands on four soil types in Hungary in order to compare their chemical element contents. The amount of rhizomorphs found in the samples increased with decreasing pH of the soil types as well as with decreasing pH caused by the influence of stemflow water. Least rhizomorphs were collected in the Ranker, whereas most were found in the stemflow areas of the pod- zolized Brown Earth. Rhizomorph and beech root samples, collected for comparison, showed highly significant differences in their chemical element contents. Rhizomorphs contained less B, Fe. Ga, Li, Mg, Mn, Ti and V, but more Cd, Co, P, Pb, Si and Zn in all soil types than comparable beech root samples. Remarkable was the high Pb content of rhizomorphs, which is not characteristic of mushroom fruiting bodies collected in unpolluted areas.     

Staphylococci isolated from animals and food with phenotypically reduced susceptibility to beta-lactamase-resistant beta-lactam antibiotics

The antibiotic resistance pattern of 1921 Staphylococcus strains isolated from animals and food within the last two years were examined using diffusion tests. Among them there were only 35 strains of S. aureus having an inhibition zone diameter of 15 mm or less, and 4 strains of coagulase-negative staphylococci (CNS) having a zone diameter of 18 mm or less to 1-microg oxacillin disk. These 39 strains were examined also by E-test to oxacillin and for the detection of the mecA gene by PCR in order to determine whether they might be real methicillin-resistant staphylococci. Among the 39 strains there were only two that were susceptible to penicillin by disk diffusion method; however, further examination by the penicillinase test showed that they produced beta-lactamase. While 19 (15 S. aureus, 4 CNS) strains were resistant and 7 strains were intermediate to oxacillin in disk diffusion test, the E-test gave 8 resistant and 5 intermediate results. Six out of the 8 oxacillin-resistant strains examined by disk diffusion and E-test harboured the mecA gene. Thus only 6 out of the examined 1921 strains proved to be mecA positive. These methicillin-resistant, mecA-positive strains (5 of the S. aureus strains and 1 of the S. epidermidis) originated from two dairy herds. The results prove that methicillin-resistant S. aureus (MRSA) strains in animals are really rare in Hungary. Eighteen strains were chosen and screened for minimal inhibitory concentration (MIC) of oxacillin with or without clavulanic acid or sulbactam, and three of them produced methicillinase enzyme.     

Energy imbalance related predisposition to mastitis in group-fed high-producing postpartum dairy cows

The energy imbalance related predisposition to mastitis was studied in group-fed postpartum dairy cows (n = 333) kept in 4 large-scale units and producing milk of low somatic cell count (SCC). Blood samples were taken on Days 1-3 after calving for assaying some metabolites and hormones related to the negative energy balance (NEB). If mastitis was diagnosed later, aseptic milk samples were taken to identify the pathogens. Considering pathogen types [contagious pathogens: Staphylococcus (S.) aureus, Gram-positive (GP) environmental pathogens, and Gram-negative (GN) environmental pathogens + mastitis with no detectable pathogens (NDP)] separately, stepwise logistic regression was used to analyse the relation between the potential prognostic value of hormones and metabolites and mastitis outbreak. Only the elevated (> or = 1.00 mmol/l) serum beta-hydroxybutyrate (BHB) levels predisposed the cows to mastitis in the subsequent 4 weeks. This prognostic value of BHB was significant only in GN + NDP mastitis and in cases caused by GP environmental pathogens, but not in S. aureus mastitis (odds ratio: 5.333, 3.600 and 1.333, respectively).     

Binding of mycoplasmas to solid phase adsorbents

The capture of mycoplasmas (M. hominis, M. buccale, M. fermentans, M. bovis, M. synoviae, M. gallisepticum and M. arthritidis) based on lipid structures and adhesion molecules present in the mycoplasmal membrane was tested using different chromatographic resins (ActiClean Etox, ClarEtox, Heparin-Actigel, Sulfated Hiflow and SulfEtox). All of the resins efficiently reduced mycoplasma concentrations in Phosphate Buffered Saline (PBS) and in Fetal Bovine Serum (FBS) by 3-8 logs in a few minutes. This technology could be used for removing mycoplasmas from tissue culture components such as serum, and for concentrating mycoplasmas in vaccine production.