Bemerkungen zum Waldsterben und Umweltschutz in der Schweiz     

J. B. Bucher 《European Journal of Forest Research》1984,103(1):16-27

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Reduction of behavioural disturbances in elderly dogs supplemented with a standardised Ginkgo leaf extract     

Reichling J  Frater-Schröder M  Herzog K  Bucher S  Saller R 《Schweizer Archiv für Tierheilkunde》2006,148(5):257-263

In this open clinical trial conducted in 10 veterinary practices, Ginkgo leaf extract was administered as a dietary supplement to 42 elderly dogs (mean age 11.4 years) at a daily dose of 40 mg/ 10 kg body weight for 8 weeks. The "severity of the geriatric condition" in dogs with a history of geriatric behavioural disturbances (mean duration 12 months), was significantly reduced after 8 weeks of treatment (P = 0.0002). The positive effect was already apparent after 4 weeks. Thirty-six % of the dogs were completely free of clinical signs at study end. Overall efficacy of treatment as judged by the investigator was good or very good in 79% of the dogs. Five of six clinical sign scores (disorientation, sleep/activity changes, behavioural changes, general behaviour and general physical condition/vitality) also showed a significant decrease over the treatment period. In conclusion, these findings provide promising results that could increase the quality of life in the elderly dog and, as a consequence, that of the pet owner. The Ginkgo leaf extract appears to be an efficacious agent that provides a safe dietary supplement for the elderly dog with age-related behavioural disturbances.  相似文献   

Sacral osteochondrosis in two German Shepherd Dogs   总被引：1，自引：1，他引：0  

KR Mathis  M Havlicek  JB Beck  RD Eaton-Wells  FM Park 《Australian veterinary journal》2009,87(6):249-252

Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia.  相似文献   

Assessment of welfare of suckling lambs following intradermal injection of cetrimide as a non-surgical alternative to conventional mulesing     

IG Colditz  JB Lloyd  DR Paull  C Lee  A Giraudo  C Pizzato  AD Fisher 《Australian veterinary journal》2009,87(1-2):12-18

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Retention and Leaching of Elevated N Deposition in a Forest Ecosystem with Gleysols     

Hagedorn  Frank  Schleppi  Patrick  Bucher  Jürg  Flühler  Hannes 《Water, air, and soil pollution》2001,129(1-4):119-142

The responses of nitrogen transformations and nitrate (NO_{_3} ^-) leaching to experimentally increased N deposition were studied in forested sub-catchments (1500 m²) with Gleysols in Central Switzerland. The aim was toinvestigate whether the increase in NO₃ ^- leaching,due to elevated N deposition, was hydrologically driven orresulted from N saturation of the forest ecosystem.Three years of continuous N addition at a rate of 30 kgNH₄NO₃-N ha^-1 yr^-1 had no effects on bulksoil N, on microbial biomass N, on K₂SO₄-extractableN concentrations in the soil, and on net nitrification rates.In contrast, N losses from the ecosystem through denitrification and NO₃ ^- leaching increased significantly. Nitrate leaching was 4 kg N ha^-1yr^-1at an ambient N deposition of 18 kg N ha^-1 yr^-1.Leaching of NO₃ ^- at elevated N deposition was 8 kg Nha^-1 yr^-1. Highest NO₃ ^- leaching occurredduring snowmelt. Ammonium was effectively retained within theuppermost centimetres of the soil as shown by the absence ofNH₄ ⁺ in the soil solution collected with microsuction cups. Quantifying the N fluxes indicated that 80% ofthe added N were retained in the forest ecosystem.Discharge and NO₃ ^- concentrations of the outflow from the sub-catchments responded to rainfall within 30 min. The water chemistry of the sub-catchment outflow showed thatduring storms, a large part of the runoff from this Gleysol derived from precipitation and from water which had interactedonly with the topsoil. This suggests a dominance of near-surface flow and/or preferential transport through this soil. The contact time of the water with the soil matrix wassufficient to retain NH₄ ⁺, but insufficient for a complete retention of NO₃ ^-. At this site with soilsclose to water saturation, the increase in NO₃ ^- leaching by 4 kg N ha^-1 yr^-1 through elevated N inputsappeared to be due to the bypassing of the soil and the rootsystem rather than to a soil-internal N surplus.  相似文献   

Microbial succession in litter decomposition in the semi-arid Chaco woodland     

P.A. Torres  E.H. Bucher 《Soil biology & biochemistry》2005,37(1):49-54

Microbial succession associated with litter decomposition was studied in the semi-arid western Chaco woodland of Cordoba province, Argentina. Annual rainfall in the area averages 450 mm, concentrated during the summer (October-March). We placed 200 g of freshly shed litter in metallic cages covered with 1 mm mesh divided in four equal size sectors, for 1 year. Cages were sampled at 3-month intervals from the starting date. On each sampling date, we collected the content of one sector from each cage for analysis. Microbial functional groups (ammonifiers, nitrifiers, N-fixing, cellulolytic, and sugar fungi) and litter chemical composition (carbon, nitrogen, insoluble fibre, and phenol concentration) were analysed in the initial litter and litter samples collected at the end of each sampling period. Litter mass remained constant during the dry season (winter and spring), decreasing abruptly in the wet season (summer and autumn). Nitrogen content increased significantly until summer (from 1.52 to 2.18%), whereas phenols and C/N ratio decreased (from 2.48 to 0.67 and from 40 to 20%, respectively). Sugar fungi and ammonifiers increased rapidly since the initial stages and remained stable throughout the year (from log 5.0 to log 6.2 and from log 5.4 to log 20.0, respectively). Cellulolytic bacteria and fungi as well as nitrifiers decreased markedly during winter and spring, peaking in summer. Nitrogen-fixing bacteria increased during the study period (from log 1.6 to log 4.8), showing a significant correlation with ammonifiers, C/N ratio, and N content (r²=0.801, 0.573 and 0.513, respectively). Our results show that microbial successions in litter decomposition are strongly influenced by synergic interaction among functional groups and litter chemical composition. Moreover, they also suggest that biological nitrogen fixation may have an important role in improving the C/N ratio, and therefore favours a higher decomposition rate.  相似文献   

Characterization of phytoavailable zinc in compost-peat substrates — Comparison of methods     

Annette S. Bucher  Manfred K. Schenk 《植物养料与土壤学杂志》1997,160(5):595-601

Compost of separately collected green yard and organic household wastes may contain high amounts of Zn. Hence, substrates basing on compost can result in Zn phytotoxicity. The aim of the investigations was to identify a suitable reagent to characterize phytoavailable Zn in compost-peat substrates. Petunia hybrids were cultivated in compost-peat substrates with increasing Zn amounts (basic load, 400, 800, 1600 mg kg^?1 d.m. aqua regia soluble). Extractable Zn was determined by extraction of fresh and dried substrates with H₂O, 1 M NH₄NO₃, 0.1 M CaCl₂, 1 M NH₄OAc, and CaCl₂-DTPA (0.01 M + 0.002 M). The Zn content of plants increased significantly with increasing Zn application and decreasing pH. The result of CaCl₂ and NH₄OAc extraction reflected the influence of pH on Zn phytoavailability quite well and the correlation with the plant Zn content was very good. Extraction with H₂O and NH₄NO₃ did not give acceptable results. Extraction with CaCl₂-DTPA was inconsistent for all trials and thus not suitable. The percentage of CaCl₂-extractable Zn in relation to the aqua regia soluble content at the same pH varied over the trials. Thus, the phytoavailable content of the substrates is influenced by additional factors, besides Zn supply and pH. The result of CaCl₂ extraction of dried substrates resulted in the best reflection of Zn phytoavailability and was used for all further investigations, including determination of critical values of phytotoxic Zn. Plant yield was not influenced by the Zn treatments. However, Zn induced chlorosis of petunias occurred at a plant Zn content > 160 mg kg^?1 d.m. and a phytoavailable Zn content in the substrate > 6 mg l^?1 in CaCl₂ extract and > 2.6 mg l^?1 in NH₄OAc extract, respectively.  相似文献   

Dynamics of Oxidation of a Fe2+-Bearing Aluminosilicate (Basaltic) Melt     

RF Cooper  JB Fanselow  JKR Weber  DR Merkley  DB Poker 《Science (New York, N.Y.)》1996,274(5290):1173-1176

Rutherford backscattering spectroscopy (RBS) and microscopy demonstrate that the approximately 1400°C oxidation of levitated droplets of a natural Fe2+-bearing aluminosilicate (basalt) melt occurs by chemical diffusion of Fe2+ and Ca2+ to the free surface of the droplet; internal oxidation of the melt results from the required counterflux of electron holes. Diffusion of an oxygen species is not required. Oxidation causes the droplets to go subsolidus; magnetite (Fe3O4) forms at the oxidation-solidification front with a morphology suggestive of a Liesegang-band nucleation process.  相似文献   

Platinum-group element abundance patterns in different mantle environments     

M Rehkamper  AN Halliday  D Barfod  JG Fitton  JB Dawson 《Science (New York, N.Y.)》1997,278(5343):1595-1598

Mantle-derived xenoliths from the Cameroon Line and northern Tanzania display differences in their platinum-group element (PGE) abundance patterns. The Cameroon Line lherzolites have uniform PGE patterns indicating a homogeneous upper mantle over several hundreds of kilometers, with approximately chondritic PGE ratios. The PGE patterns of the Tanzanian peridotites are similar to the PGE systematics of ultramafic rocks from ophiolites. The differences can be explained if the northern Tanzanian lithosphere developed in a fluid-rich suprasubduction zone environment, whereas the Cameroon Line lithosphere only experienced melt extraction from anhydrous peridotites.  相似文献   

Pregnancy Rates in Angus Cross Beef Cows Bred at Observed Oestrus With or Without Second GnRH Administration in Fixed‐Time Progesterone‐Supplemented Ovsynch and CO‐Synch Protocols     

R Kasimanickam  JB Hall  JF Currin  B Inman  JS Rudolph  WD Whittier 《Reproduction in domestic animals》2010,45(3):487-492

Crossbred cows (n = 1073) from five locations had oestrous cycles synchronized with 100 μg of GnRH IM and insertion of controlled internal drug release device (CIDR) on Day 0 followed by 25 mg of PGF_2α IM and CIDR removal on Day 7. Kamar^® patches were placed on all cows at CIDR removal. Cows were observed three times daily for oestrus after PGF_2α administration. In the Ovsynch‐CIDR group, cows detected in oestrus (n = 193) within 48 h after PGF_2α were inseminated using the AM–PM rule. Among these cows, 80 received and 113 did not receive a second GnRH at 48 h after PGF_2α. Cows (n = 345) not detected in oestrus received a second GnRH at 48 h after PGF_2α on Day 9, and fixed‐time AI 16 h after the GnRH on Day 10. In the CO‐Synch‐CIDR group, cows detected in oestrus (n = 224) within 48 h after PGF_2α were inseminated using the AM–PM rule. Among these cows, 79 received and 145 did not receive a second GnRH at 64 h after PGF_2α. Cows (n = 311) not detected in oestrus received a second GnRH on Day 10 at the time of AI, 64 h after PGF_2α. The AI pregnancy rates were not different between the Ovsynch‐CIDR and CO‐Synch‐CIDR groups (p = 0.48). There were no differences in the AI pregnancy rates for cows inseminated at a fixed time (p = 0.26) or at detected oestrus (p = 0.79) between the treatment groups. Among cows inseminated in oestrus, there were no differences in the AI pregnancy rates between cows that received or did not receive the second GnRH (p = 0.47). In conclusion, acceptable AI pregnancy rates can be achieved with or without inclusion of oestrus detection in the Ovsynch‐CIDR and CO‐Synch‐CIDR protocols. Among cows detected in oestrus, cows that received a second GnRH yielded similar pregnancy rates when compared with cows that did not receive the second GnRH.  相似文献