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Braunschweig, Germany

Piesova E.,University of Veterinary Medicine in Kosice | Makova Z.,University of Veterinary Medicine in Kosice | Levkut M.,University of Veterinary Medicine in Kosice | Faixova Z.,University of Veterinary Medicine in Kosice | And 2 more authors.
Research in Veterinary Science

We investigated the effects of dietary addition of sage extract on the biochemical parameters, weight of some body organs and changes in the counts of Salmonella Enteritidis PT4 (SE) in experimentally infected chickens. The following diets were used: basal diet, basal diet with addition of an extract of Salvia officinalis L. (S), basal diet and SE, and basal diet and S and SE (SSE). Compared to the SE group, sage extract in the SSE group decreased activities of ALP and ALT and concentrations of glucose and bilirubin on the 4th day post inoculation (p.i.). However, on the 18th day p.i., lower levels of bilirubin and ALT activity only were detected. Addition of sage extract to the diets decreased the counts of Salmonella in the liver, spleen and caecum at both sampling times, along with lower production of mucus in the chickens' intestines. Our results suggest that the addition of sage extract to the diet could be effective in protecting SE-infected chickens. © 2012 Elsevier Ltd. Source

Anderson T.-H.,Federal Research Institute for Rural Areas | Anderson T.-H.,Institute of Agroecology | Anderson T.-H.,Institute of Soil Biology | Domsch K.H.,Institute of Soil Biology
Soil Biology and Biochemistry

In the 1980s ecosystem research projects were implemented world-wide since there was a pressing need to quantify the impacts of anthropogenic pollutants. Soil ecosystem analyses concentrated first on the quantification of the element and energy transfer between pools. Since mineralization of organic substrates and the release of nutrients and elements are due to the heterotrophic activity of the microbial decomposer compartment, this subsystem of terrestrial ecosystems gained importance. Direct microscopic observation methods were inadequate for the quantification of environmental impacts on the microflora. We adopted the maintenance requirement concept for the quantification of environmental impacts or stress effects on the soil microbial community. The paper gives a brief inside to the concept of maintenance from autecological studies and describes the underlying points which lead to our experimental approach of its application at the synecological level (i.e., microbial biomass as a single ecological entity) - a process which rested on long-term continuous research. © 2010 Elsevier Ltd. Source

Anderson T.-H.,Institute of Agroecology | Anderson T.-H.,Institute of Agricultural Climate Research | Martens R.,Institute of Agroecology | Martens R.,Institute of Biodiversity
Soil Biology and Biochemistry

We attempted to quantify microbial growth in soil by means of DNA determination after glucose amendment. An FDNA conversion factor of 5.0 was used to convert μg DNA g-1 soil to μg Cmic g-1 soil during the growth phase. The conversion factor acquired rested on a regression analysis between soil microbial biomass-C (Cmic) estimated by the substrate-induced respiration technique (SIR) and dsDNA using a modified, miniaturized dsDNA extraction procedure which included 44 field and forest soils with a coefficient of determination of r2 = 0.95. Verification of this conversion factor was tested on eight arable soils where Cmic was determined by substrate-induced respiration (SIR)-, chloroform fumigation-incubation (CFI)-, chloroform fumigation-extraction (CFE)-, and application of the FDNA conversion factor. The congruency between the Cmic values obtained through these different techniques was satisfactory since five of eight soils gave similar Cmic values which were not statistically significantly different. The soils were thereafter amended with glucose and microbial growth followed by Cmic determinations with CFI, CFE, and DNA conversion over a period of up to 264 h at 22 °C. Concomitant CO2 analyses gave clues to two kinds of growth processes with respect to speed. Based on DNA conversion the calculated traditional growth parameters such as the specific growth rate (μ) lay in the range between 0.0046 and 0.022 h-1 which is several fold slower than μ values based on CO2 conversion but are in accordance with data in the earlier literature on growth rates for bacteria and fungi in soil done with traditional plate counts. These results suggest that DNA determinations can be applied as an alternative index for growth studies in situ. © 2012 Elsevier Ltd. Source

Anderson T.-H.,Institute of Agroecology | Anderson T.-H.,Institute of Biodiversity | Heinemeyer O.,Institute of Agroecology | Heinemeyer O.,Institute of Agricultural Climate Research | And 2 more authors.
Soil Biology and Biochemistry

In soil ecology, microbial parameters have been identified as sensitive indicators of changes in the soil environment. The Braunschweig FACE project provided the opportunity to study the effects of elevated CO2 (550 μmol mol-1) as compared to ambient CO2 (370 μmol mol-1) on total microbial biomass (Cmic), Cmic-to-Corg ratio and the fungal-to-bacterial respiratory ratio together with total Corg, Nt, C:N ratio and pH over a six-year period. Field management followed a typical crop rotation system of this region with either a crop-related full nitrogen supply (N100) or 50% reduced N supply (N50). The soil microbial parameters responded to the elevated CO2 treatment in varying intensities and time spans. The fungal-to-bacterial respiratory ratio was the most sensitive parameter in responding to an elevated CO2 treatment with highly significant differences to ambient CO2-treated control plots in the third year of CO2 fumigation. After six years bacterial respiratory activity had increased in ascending order to 34% in FACE-treated plots (N50 and N100) as compared to control plots. Soil microbial biomass (Cmic) responded more slowly to the FACE treatment with highly significant increases of >12% after the fourth year of CO2 fumigation. The Cmic-to-Corg ratio responded very late in the last two years of the CO2 treatment with a significant increase of >7.0% only in the N100 variant. Total Corg and Nt were slightly but significantly increased under FACE around 10.0% with ascending tendency over time starting with the second year of CO2 treatment. No significant FACE effects could be recorded for the C:N ratio or pH.These results suggest that under FACE treatment changes in the soil microbial community will occur. In our study the fungal-to-bacterial respiratory ratio was superior to total Cmic as microbial bioindicators in reflecting changes in the soil organic matter composition. © 2011 Elsevier Ltd. Source

Bach M.,Justus Liebig University | Diesner M.,German Federal Environment Agency UBA | Grossmann D.,German Federal Environment Agency UBA | Guerniche D.,Institute of Agroecology | And 8 more authors.
Pest Management Science

In 2001, the European Commission introduced a risk assessment project known as FOCUS (FOrum for the Coordination of pesticide fate models and their USe) for the surface water risk assessment of active substances in the European Union. Even for the national authorisation of plant protection products (PPPs), the vast majority of EU member states still refer to the four runoff and six drainage scenarios selected by the FOCUS Surface Water Workgroup. However, our study, as well as the European Food Safety Authority (EFSA), has stated the need for various improvements. Current developments in pesticide exposure assessment mainly relate to two processes. Firstly, predicted environmental concentrations (PECs) of pesticides are calculated by introducing model input variables such as weather conditions, soil properties and substance fate parameters that have a probabilistic nature. Secondly, spatially distributed PECs for soil-climate scenarios are derived on the basis of an analysis of geodata. Such approaches facilitate the calculation of a spatiotemporal cumulative distribution function (CDF) of PECs for a given area of interest and are subsequently used to determine an exposure concentration endpoint as a given percentile of the CDF. For national PPP authorisation, we propose that, in the future, exposure endpoints should be determined from the overall known statistical PEC population for an area of interest, and derived for soil and climate conditions specific to the particular member state. © 2016 Society of Chemical Industry. Source

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