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971.
To investigate further the occurrence of fear-related behaviour in dogs in veterinary practice and to evaluate associated factors, 135 dogs were observed under practice conditions within the framework of a standardised test examination and the owners interviewed using a questionnaire. Most dogs exhibited fear reactions, particularly on the examination table, with 78.5% (106/135) categorised as ‘fearful’ based on their behaviour. Unlike weight and castration, age, gender and previous experience were significantly (P < 0.05) associated with fearful behaviour. Male dogs were significantly less ‘fearful’ than females and animals under <2 years were significantly less ‘fearful’ compared with older dogs. Those with only positive previous experiences in veterinary surgeries were significantly less ‘fearful’ than dogs that had a previous negative experience. Fear-related behaviour in veterinary practice is an issue of importance.  相似文献   
972.

Purpose  

Although the challenge of linking pedology and hydrology has been identified recently, the microbial diversity in floodplain soils has been studied little in comparison to terrestrial soils. In terrestrial soils, the relationship between soil microbial biomass (SMB) determined by substrate-induced respiration (SIR) and phospholipid fatty acids (PLFA) was examined in several studies. Floodplain soils reveal substantially different properties; they are exposed to drastic changes in water regime from flooded to dry conditions. The relation between SMB determined by SIR and PLFA has, up to the present, not been adequately proved in floodplain soils. Thus, this study was conducted to elucidate the relationship between SMB determined with both methods in a set of floodplain soils of eleven study sites from three study areas along the Elbe River (Germany).  相似文献   
973.

Purpose  

The significance of chironomids mouthpart deformities as suitable indicators for pollutant contamination of natural waters and sediments has been investigated and discussed for several decades. Uncertainties still exist as further laboratory studies, with different pollutants and with the same experimental design are required.  相似文献   
974.
The phosphorus (P) speciation of organic surface layers from two adjacent German forest soils with different degree of water‐logging (Stagnosol, Rheic Histosol) was analyzed by P K‐edge XANES and subsequent Linear Combination Fitting. In both soils, ≈ 70% of the P was inorganic phosphate and ≈ 30% organic phosphate; reduced P forms such as phosphonate were absent. The increased degree of water‐logging in the Histosol compared to the Stagnosol did not affect P speciation.  相似文献   
975.
This study was conducted to improve our understanding of how earthworms and microorganisms interact in the decomposition of litter of low quality (high C : N ratio) grown under elevated atmospheric [CO2]. A microcosm approach was used to investigate the influence of endogeic earthworm (Aporrectodea caliginosa Savigny) activity on the decomposition of senescent Charlock mustard (Sinapis arvensis L.) litter produced under ambient and elevated [CO2]. Earthworms and microorganisms were exposed to litter which had changed in quality (C : N ratio) while growing under elevated [CO2]. After 50 d of incubation in microcosms, C mineralization (CO2 production) in the treatment with elevated‐[CO2] litter was significantly lower in comparison to the ambient‐[CO2] litter treatment. The input of Charlock mustard litter into the soil generally induced N immobilization and reduced N2O‐emission rates from soil. Earthworm activity enhanced CO2 production, but there was no relationship to litter quality. Although earthworm biomass was not affected by the lower quality of the elevated‐[CO2] litter, soil microbial biomass (Cmic, Nmic) was significantly decreased. Earthworms reduced Cmic and fungal biomass, the latter only in treatments without litter. Our study clearly showed that A. caliginosa used the litter grown under different [CO2] independent of its quality and that their effect on the litter‐decomposition process was also independent of litter quality. Soil microorganisms were shown to negatively react to small changes in Charlock mustard litter quality; therefore we expect that microbially mediated C and N cycling may change under future atmospheric [CO2].  相似文献   
976.

Purpose  

The aim of the present study was to investigate possible relationships between the sediment contaminants and the occurrence of intersex in situ. Two of the studied sediments were from polluted sites with increased occurrence of intersex crustaceans (Lake Pilnok, black coal mining area in the Czech Republic, inhabited by the crayfish Pontastacus leptodactylus population with 18% of intersex; creek Lockwitzbach in Germany with Gammarus fossarum population with about 7% of intersex).  相似文献   
977.
978.
979.

Purpose  

Although ivermectin is a widely used lipophilic parasiticide, data on its potential bioaccumulation in aquatic invertebrates are scarce. In this study, bioaccumulation patterns of radiolabeled 3H-ivermectin from sediments into tissues of the sediment-dwelling worm Lumbriculus variegatus were investigated and assessed.  相似文献   
980.

Background, aim, and scope  

Plant growth and productivity under abiotic stresses such as water shortage or pollution are major problems which currently worry scientists in the field of food production and plant health. Since the intensification of livestock production with its associated increased demand for fodder has encouraged farmers to rely more heavily on chemical fertilizers, very often, municipal waste and wastewater sludge is considered a possible source of plant nutrients, although it might carry a significant amount of anthropogeneous pollutants. The extent to which plants react to drought, as well as how pollutants are taken up or how they act on plants, might depend on rhizosphere processes such as mycorrhizal symbioses. Therefore, it seemed timely to investigate plant defense reactions in the presence of arbuscular mycorrhizal fungi (AMF) toward a possible dangerous sewage sludge pollutant under the influence of drought.  相似文献   
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