Quantitative resistance level (MIC) of Escherichia coli isolated from calves and pigs suffering from enteritis: national resistance monitoring by the BVL

National Resistance Monitoring of the Federal Office of Consumer Protection and Food Safety (BVL), which was put into service in 2001, has made it possible to implement a valid and representative database on the basis of which the resistance situation, development and spread in animal pathogens can be evaluated. Escherichia coil (E. coli) strains originating from calves and pigs suffering from enteritis were first included in the investigations in the 2004/2005 study. A total of 258 bovine and 492 porcine E. coli strains were tested using the broth microdilution method to determine the in vitro susceptibility (minimum inhibitory concentration) to 23 (fattening pigs) and 28 (calves, piglets, weaners) different antimicrobial substances. Considerable prevalences of resistance were found for some antimicrobials. The strains originating from both animal species displayed high prevalences of resistance for tetracycline, trimethoprim, trimethoprim/sulfamethoxazole, doxycycline and ampicillin. Reduced susceptibility was detected particularly in the E. coli strains from calves. The data reveal that the resistance level of E. coli strains isolated from cases of enteric disease in calves and pigs is altogether higher than has so far been reported in pathogens causing different diseases and in other food-producing animal species. Based on the results presented, it is possible to assess the current resistance situation for E. coli strains in calves and pigs in Germany. This in turn helps to deduce the necessary management measures that can be taken in order to minimise resistance to antibiotics. Furthermore, the data help to decide on adequate therapy of E. coli infections of the intestinal tract in calves and pigs and encourage the responsible use of antibiotics in the interests of animal health and consumer protection.     

Quantitative resistance level (MIC) of bacterial pathogens (Escherichia coli, Pasteurella multocida, Pseudomonas aeruginosa, Salmonella sp., Staphylococcus aureus) isolated from chickens and turkeys: national resistance monitoring by the BVL 2004/2005

In the study 2004/2005, the current quantitative resistance level of Escherichia coli, Pasteurella multocida, Pseudomonas aeruginosa, Salmonella sp. and Staphylococcus aureus from chickens and turkeys was determined for the first time within the framework of the National Resistance Monitoring of the Federal Office of Consumer Protection and Food Safety (BVL).The objective was to implement a valid database on the basis of which the development and spread of resistance can be evaluated and monitored. During the investigation period from January 2004 to February 2005,927 strains were collected and 857 (92%) bacteria strains which corresponded to the specifications of the study protocol were tested with the broth microdilution method to determine the in vitro susceptibility (minimum inhibitory concentration) to 22 to 28 antimicrobial agents or antibiotic combinations. The results document a prevalence of resistance that exceeds that of bacterial pathogens of other animal species, especially in the case of tetracycline. Apart for S. aureus, clinical resistance to fluoroquinolones can still be considered low in poultry pathogens (E. coli approx. 2%). By applying the MICG of 4 mg/L for enrofloxacin, a susceptibility of approximately 78 % was calculated for S. aureus. A comparison of the prevalence of resistance between chickens and turkeys, showed that a slightly higher prevalence of resistance can be expected in turkeys. Differences between the susceptibility data of chicks and adult animals could only be found in turkeys. In the case of E. coli, the prevalence of resistance of strains isolated from adult turkeys was up to 10% higher than those isolated from chicks for the corresponding antimicrobial agents. It must be pointed out that the number of E. coli strains from adult turkeys was much higher (n = 194) than the number from turkey chicks (n = 21). The results indicate clearly that in a resistance monitoring system it is necessary to categorise poultry by animal species (chicken, turkey) as well as by production stage and type (broiler, laying hen), so that the epidemiology of resistance can be correctly represented and evaluated. This information is the basis for the development of long-term management options for minimizing antibiotic resistance. Furthermore, the knowledge of prevailing resistance levels in Germany is a valuable tool for veterinary practitioners when determining an empirical therapy.The data collected by the BVL make an important contribution to the optimisation of the safety of food from animals, and thus to improving consumer protection.     

No evidence of superclones in leaf-feeding forms of austrian grape phylloxera (Daktulosphaira vitifoliae)

European Journal of Plant Pathology - The genetic structure of ten grape phylloxera populations, sampled in summer of 2006 and 2007 from four distinct viticultural areas in Austria, Daktulosphaira...     

Influence of liming on the epigeic spider (Araneae) community of the Krušné hory Mts. (Czech Republic)

We studied the influence of liming with the dolomitic limestone on the epigeic spider community in the birch stand of the Krušné hory Mts. in the Czech Republic. The treatment was carried out with the purpose of reducing the negative effect of anthropogenic air pollution and consequently to increase the ecological stability of the wood stand. Lime treatment in different amounts (6, 3, 1.5 and 0 t ha⁻¹) was applied in August 2003 and for the following three years the spider community was investigated. We compared occurrences of spiders on studied plots with different lime treatment and tested the influence of the environmental factors, altogether with liming, on the spider community. The most significant factor appeared to be the character of habitat and both, hierarchical cluster analysis and canonical correspondence analysis, did not confirm any significant feedback of liming to the spider community in birch stand of the Krušné hory Mts.     

Impact of water scarcity on spruce and beech forests

One of the greatest threats posed by ongoing climate change may be regarded the drought caused by changes in precipitation distribution. The aim of presented study was to characterize reactions to dry conditions and conditions without drought stress on gross primary production (GPP) and net ecosystem production (NEP) of spruce and beech forests, as these two species dominate within the European continent. Daily courses of GPP and NEP of these two species were evaluated in relation to an expected decrease in CO2 uptake during dry days. The occurrence of CO2 uptake hysteresis in daily production was also investigated. Our study was performed at Bily Kriz(spruce) and Stitna(beech) mountain forest sites during 2010–2012 period. We applied eddy covariance technique for the estimation of carbon fluxes, vapor pressure deficit and precipitation characteristics together with the SoilClim model for the determination of drought conditions, and the inverse of the Penman–Monteith equation to compute canopy conductance. Significant differences were found in response to reduced water supply for both species. Spruce reacts by closing its stomata before noon and maintaining a reduced photosynthetic activity for the rest of the day, while beech keeps its stomata open as long as possible and slightly reduces photosynthetic activity evenly throughout the entire day. In the spruce forest, we found substantial hysteresis in the light response curve of GPP. In the beech forest, the shape of this curve was different: evening values exceeded morning values.     

Safety and efficacy of sFilm-FS,a novel biodegradable fibrin sealant,in Göttingen minipigs

Bleeding during surgical procedures is a common complication. Therefore, hemostatic agents have been developed to control bleeding, and fibrin sealants have several benefits. sFilm-FS is a novel fibrin sealant that comprises a biodegradable co-polymeric film embedded with human fibrinogen and thrombin. Herein, the safety and efficacy of sFilm-FS were compared using a liver and spleen puncture model of Göttingen minipigs with those of the standard hemostatic techniques (control animals) and EVARREST^®, a reference fibrin sealant. Hemostasis and reduced blood loss were more effectively achieved with sFilm-FS than with the standard techniques in the control animals and comparable to those achieved with EVARREST^®. No treatment-related adverse effects were observed in any of the groups. Histopathological evaluation indicated that sFilm-FS was slightly and moderately reactive at the liver puncture site and spleen, respectively, compared with the standard techniques in the control animals. These changes are expected degradation reactions of the co-polymeric film and are not considered as adverse events. No treatment-related abnormalities were noted in the other evaluated organs. Additionally, no evidence of local or systemic thromboses was noted. These results support the use of sFilm-FS for hemostasis in humans.     

Seasonal development of above‐ and below‐ground organs of Trifolium pratense in grass–legume mixture on different soils

Grass–legume mixtures are suitable for crop rotations in organic farming. However, seasonal development of below‐ground organs of Trifolium pratense in mixtures and on different soils was neglected. We asked (1) how the diameter of the root neck, the maximum order of branching as well as (2) the nodule traits are affected by locality and time, and (3) how above‐ground plant traits of red clover vary in space and time. Red clover was investigated in grass–legume mixtures in the first year of vegetation. Five sites in S Germany were sampled at the day of cut at the end of May, the beginning of July, and at the end of August, respectively. Under similar climatic conditions root traits (diameter of the root neck, order of root branching, size of nodules, and proportion of senescent nodules) differed with soil conditions and time within the season. Root diameter increased during the season. Higher sand content fostered root branching and branched roots developed more nodules. Thinner roots had more active nodules (pink). Root diameter and non‐active senescent (green) or moribund (brown) nodules increased at the end of season. Nodule activity differed more according to season than to soil conditions. The number of nodules per plant (12.5–19.5) decreased from May to August. Cylindrical nodules were found on 85–100% of the plants and branched nodules only on 0–25%. The height of plants was lowest in May and increased in July. The mean number of stems per plant (3.3–6.3) was highest in August. Understanding red clover traits and N₂ fixation is interesting scientifically as well as agronomical. Organic and conventional farmers can both benefit of our findings.     

Simplified performance assessment methodology for addressing soil quality of nature-based solutions

Journal of Soils and Sediments - In urban areas, soil functions are deeply impacted by all human activities, e.g., water infiltration, carbon storage, and chemical substances degradation potential....     

Monitoring of root‐zone water content in the laboratory by 2D geoelectrical tomography

Root water uptake is one of the essential processes within the soil–plant–atmosphere continuum. We present a method for monitoring soil‐water redistributions due to water uptake by roots. Our aim is to image and monitor diurnal soil‐water redistribution during a small‐scale (centimeter‐to‐decimeter range) indoor experiment and to correlate water content determined by applied geoelectrical time‐lapse imaging techniques with values from single‐point time domain reflectometry (TDR) measurements. This includes establishing pedophysical relationships within the root zone and deriving the water‐content distribution from the electrical‐resistivity model. Using DC geoelectrics of high resolution (970 data points for 220 cm²), we monitored significant spatial heterogeneity of soil moisture with time, whereas no irrigation was applied. Thus, we imaged the high heterogeneity of fluid movements within the soil. We found diurnal variations with high spatial variability of soil water content during the morning and afternoon hours. The water content continuously increased from dawn to noon, whereas the increase started in the near‐surface zone from 1 cm to 3 cm above the main root zone. Between 8:00 a.m. and 10:00 a.m., water content decreases along most of the sections. Water content irregularly decreases and increases during the afternoon. During night time, we observed nearly no changes in soil water content due to the absence of transpiration and subsequently soil‐water redistribution. Most of these diurnal variations in soil water content lie within the intensive root zone, as measurements showed on soil samples excavated from these areas after the experiment. Furthermore, we quantified water content derived from geoelectrical tomography of the monitored area before and after an irrigation event using a geophysical pedotransfer function of Archie, established specifically for the used lupine and the applied physico‐chemical boundary conditions of the experiment. The resulting average water content from 2D geoelectrical tomography agreed well with the values determined by the TDR measurements.     

Denitrification- and Nitrate Leaching-Losses in an Intensively Cropped Watershed

In continuation of former measurements about gaseous denitrification losses, these losses together with those by nitrate leaching were measured by different methods in a field cropped during two years by wheat. Furthermore, N-uptake by the plants of fertilizer- and soil-N as well as N-im-mobilization in soils during and after the cropping periods was determined by application of highly enriched¹⁵N-labeled fertilizer. Denitrification losses determined by the N₂O release from C₂H₂–treated undisturbed soil cores agreed reasonably well with losses obtained by ¹⁵N-balance measurements. They both amounted during the cropping periods 12–15 and 6–20 kg N ha^?1, respectively. Gaseous N-losses increased mainly during wet periods when the field was barren. Denitrifying enzyme activities and soil respiration (CO₂-release) was measured throughout one year. Leaching losses of NO₃ from soil-and fertilizer-N occurred only during fall until spring. Leached NO₃^? originated mostly from mineralized soil-N and very little from previously immobilized fertilizer-N.