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61.
Walker KA Horning M Mellish JA Weary DM 《Veterinary journal (London, England : 1997)》2011,190(1):160-164
This study examined the effects of two non-steroidal anti-inflammatory drug (NSAID) treatment protocols on the behavioral responses of juvenile Steller sea lions after abdominal surgery. Sea lions were randomly assigned to one of two treatments designed to control post-operative pain. The flunixin group (n=6) received flunixin meglumine (1mg/kg) administered as a single intramuscular (IM) injection before extubation from surgery. The carprofen group (n=5) received carprofen (4.4 mg/kg) as an IM injection before extubation, then orally at 24, 48 and 72 h after surgery. Seven behaviors related to post-operative pain were monitored by observers, blinded to treatment, for a total of 10 days (3 days pre-, day of surgery, and 6 days post-surgery). All seven behaviors changed after surgery regardless of NSAID treatment, two of which returned to baseline within 6 days of surgery. Only one behavior was mildly affected by analgesic treatment: sea lions in the carprofen group tended to spend less time lying down in Days 1-3 following surgery (i.e., the days which they received oral carprofen). These results suggested that neither treatment, at the dose administered, was effective in controlling pain in the days following this surgery. 相似文献
62.
63.
Nissinen A Ibrahim M Kainulainen P Tiilikkala K Holopainen JK 《Journal of agricultural and food chemistry》2005,53(22):8631-8638
The effect of carrot psyllid (Trioza apicalis F?rster) feeding and limonene and methyl jasmonate (MeJA) treatments on the essential oil composition and headspace volatiles of carrot (Daucus carota ssp. sativus), cvs. Parano and Splendid, leaves was studied. Carrot psyllid feeding significantly increased the concentrations of sabinene, beta-pinene, and limonene, whereas limonene treatment increased the concentration of (Z)-beta-ocimene in the leaves of both cultivars. The limonene treatment significantly increased the concentration of total phenolics in the leaves of both cultivars, and MeJA treatment increased phenolic concentration in the leaves of Parano. Exogenous limonene spray did not decrease the number of carrot psyllid eggs laid either 2 or 24 h after treatment. The results suggest that carrot psyllid feeding induces changes in the endogenous monoterpene pool in the carrot leaves. Limonene and MeJA treatments affect some induced defenses of the carrot, but the exogenous limonene spray is not an effective oviposition deterrent against carrot psyllid. 相似文献
64.
Ichikawa Yoichi Hayami Hiroshi Sugiyama Taishi Amann Markus Schöpp Wolfgang 《Water, air, and soil pollution》2001,130(1-4):301-306
In order to contribute to the analysis and solution of regional scale environmental problems in East Asia, we developed a tool for the comprehensive assessment of alternative policy options to improve air quality. This tool projects the future regional energy supply, calculates the emission levels of sulfur dioxide and estimates the geographical pattern of sulfur deposition resulting from emissions. Sulfur deposition in Japan through 2030 was forecasted for various energy supply and emission control scenarios using the analysis tool. Future sulfur depositions were calculated from the source-receptor matrix for 1995 and the growth rate of emission for the source subregion. In the case of the current legislation scenario, anthropogenic SO2 emissions in East Asia would grow by 34 percent and sulfur deposition in Japan would increase by approximately 20 percent between 1995 and 2030. This increase in sulfur deposition over these 35 years is sligthly less than the contribution from volcanic emission to sulfur deposition in Japan. In the case of the hypothetical dirty scenario for China, sulfur deposition in several grids which face the Sea of Japan would double by 2030. 相似文献
65.
Background Tetracycline is a widely used antibiotic in animal production. Significant amounts of the substance reach the soil via feces,
urine and manure application. As tetracycline is a persistent compound with antibacterial activity, its presence in soil may
have undesired direct and indirect effects. These have been investigated so far focusing on effects on selected microbial
functions.
Objectives The aim of the present study was to obtain comprehensive information on potential effects of tetracycline on the soil microflora
under environmentally relevant conditions. The investigations included function and structure of the microbial biocoenosis
and the distribution of resistance genes.
Methods Pig manure rich in tetracycline resistance genes was applied to a sandy soil. This soil as well as an unamended soil were
additionally treated with several concentrations of tetracycline. The spiked soils were incubated in outdoor lysimeters for
several months. Substrate induced respiration, PLFAs, ten selected resistance genes, and the concentrations of tetracycline
were determined.
Results The test concentrations, though far exceeding environmental relevance, caused only small effects. An establishment of resistance
could not be detected. Applied resistance genes were not detectable at the end of the study even in the presence of added
tetracycline.
Conclusion Due to the high sorption capacity of the antibiotic, environmentally relevant concentrations of tetracycline do not seem to
cause undesired effects on the soil microflora. 相似文献
66.
Viewing of polar bears (Ursus maritimus) from tundra vehicles has been offered at Churchill, Manitoba since the early 1980s. This form of wildlife viewing has provided a unique and safe way for tourists to learn about polar bears. However, these activities have largely been carried out without examining possible effects on polar bear behaviour. We studied vigilance behaviour (a scanning of the immediate vicinity and beyond) of resting polar bears to evaluate impacts from tundra vehicle activity. Focal animal sampling was used to examine whether a difference in vigilance behaviour existed when vehicles were present. We recorded the numbers of head-ups, vigilance bout length, and between-bout intervals for polar bears. In general, the frequency of head-ups increased, and the between-bout intervals decreased for male bears, when vehicles were present. Female bears behaved opposite to males. The vigilance bout lengths did not differ significantly between vehicle presence and absence. Vigilance behaviour of male bears was not magnified with increasing numbers of vehicles; therefore the threshold is one vehicle. We suggest that manipulative studies be conducted to examine how distances between vehicles and bears, tundra vehicle activity in the immediate vicinity of a bear during viewing, and noise of tourists affect increased vigilance. 相似文献
67.
We used the soil‐core translocation method to investigate the effect of increased temperature on above‐ and below‐ground phytomass and organic matter in cool alpine areas. The translocation of undisturbed soil cores from a high alpine site (2525 m a.s.l.) to an alpine site near the timberline (1895 m a.s.l.) achieved an effective artificial warming of 3.3 K. From a methodological point of view, the translocation of soil cores was performed successfully. Soil cores moved to a new site at the same altitude showed no change in above‐ and below‐ground vegetation, bulk density, and soil skeleton. At both sites, soils were Haplic Podzols with a similar chemistry and clay mineralogy. At the lower elevation site, however, podzolization processes seemed to be more pronounced. As a consequence, the translocation of the soil cores probably led to a disturbance of the actual steady state that had been established after about 10,000–13,000 years of soil formation. This might have affected the adaptability of the vegetation system. Therefore, it cannot be fully excluded that the experimental design influenced the results. Translocation of soil cores from a very cool to a warmer site led to a distinct decrease in above‐ground phytomass (about –45%) over the experimental period of two years. Below‐ground phytomass significantly decreased (up to –50%) in the topsoil (0–5 cm) after artificial warming. Possible mechanisms are that roots reduced photosynthesis and hence C flow below‐ground, a reduction of soil moisture that would have led to root death (not a very probable cause, however) or an abrupt change in the radiation duration and flux which affected root growth (also not very probable). Fast climate change exceeded the ability of the above‐ground and below‐ground phytomass to adapt quickly. Whether the decrease in phytomass was a short‐term or a long‐term response to climate warming remains uncertain. Based on a gradient study (climosequence at the same locality), we hypothesize that the decreased plant productivity might be a short‐term effect. 相似文献
68.
Erich Inselsbacher Nina Hinko-Najera Umana Markus Gorfer Katrin Ripka Rebecca Hood-Novotny Wolfgang Wanek 《Soil biology & biochemistry》2010,42(2):360-372
Agricultural systems that receive high amounts of inorganic nitrogen (N) fertilizer in the form of either ammonium (NH4+), nitrate (NO3−) or a combination thereof are expected to differ in soil N transformation rates and fates of NH4+ and NO3−. Using 15N tracer techniques this study examines how crop plants and soil microbes vary in their ability to take up and compete for fertilizer N on a short time scale (hours to days). Single plants of barley (Hordeum vulgare L. cv. Morex) were grown on two agricultural soils in microcosms which received either NH4+, NO3− or NH4NO3. Within each fertilizer treatment traces of 15NH4+ and 15NO3− were added separately. During 8 days of fertilization the fate of fertilizer 15N into plants, microbial biomass and inorganic soil N pools as well as changes in gross N transformation rates were investigated. One week after fertilization 45-80% of initially applied 15N was recovered in crop plants compared to only 1-10% in soil microbes, proving that plants were the strongest competitors for fertilizer N. In terms of N uptake soil microbes out-competed plants only during the first 4 h of N application independent of soil and fertilizer N form. Within one day microbial N uptake declined substantially, probably due to carbon limitation. In both soils, plants and soil microbes took up more NO3− than NH4+ independent of initially applied N form. Surprisingly, no inhibitory effect of NH4+ on the uptake and assimilation of nitrate in both, plants and microbes, was observed, probably because fast nitrification rates led to a swift depletion of the ammonium pool. Compared to plant and microbial NH4+ uptake rates, gross nitrification rates were 3-75-fold higher, indicating that nitrifiers were the strongest competitors for NH4+ in both soils. The rapid conversion of NH4+ to NO3− and preferential use of NO3− by soil microbes suggest that in agricultural systems with high inorganic N fertilizer inputs the soil microbial community could adapt to high concentrations of NO3− and shift towards enhanced reliance on NO3− for their N supply. 相似文献
69.
Haufe HC Gygax L Wechsler B Stauffacher M Friedli K 《Preventive veterinary medicine》2012,105(1-2):85-92
In this study, the effects on the claw health of dairy cows of three different floor types and access to pasture were investigated on 35 farms. The farms were fitted with a given floor type in the indoor walking area of a cubicle housing system: a solid rubber, mastic asphalt or slatted concrete floor. Because we chose farms on which the given floor type was in good condition, the data presented show what can be achieved on these types of floors under ideal circumstances. Cows on half of the farms per floor type had access to pasture during the grazing period. Each farm was visited three times at approx. 6-month intervals at the end of the winter indoor-housing period and at the end of the summer period, i.e. after the period with access to pasture on half of the farms. During each visit, the claw health of the same 10 cows per farm was assessed on the occasion of routine claw trimming. The proportion of cows with haemorrhages increased from mastic asphalt to rubber and slatted concrete floors. A lower proportion of cows kept on mastic asphalt was affected by white-line fissures and needed intermittent claw-trimming, an indicator for lameness. Cows housed in cubicle systems with slatted concrete floors were at the lowest risk of having heel-horn erosions. Access to pasture was associated with a lower incidence of slight white-line fissures and dermatitis digitalis. A higher proportion of cows with sole haemorrhages and sole ulcers were found on all floor types at the end of the summer period than at the end of the winter indoor-housing period. Floor type did not influence the presence of sole ulcers and deep white-line fissures. In conclusion, the effect of floor type on claw health was slight, and none of the investigated floor types was clearly superior to the others. Access to pasture was not effective in reducing the presence of most types of claw lesions associated with the floor type used in the indoor walking area. 相似文献
70.
The European corn borer (Ostrinia nubilalis) is one of the most important pests of maize (Zea mays). Injuries to the plants caused by the larvae of the European corn borer may represent entrance gates for fungal-spores. The cultivation of Bacillus thuringiensis maize (Bt-maize) is one possibility to reduce infestation by the European corn borer. The aim of the present project was to determine and to compare the number of species and the frequency of Fusarium spp. infestation in Bt-maize (cry1Ab) and conventional maize. In 2003, we analysed the Fusarium spp. infestation of samples of chaffed Bt-maize and its isogenic variety on two experimental fields in the Oderbruch region (Germany), an European corn borer infested area. The conventional variety on the first of the experimental fields (previous crop wheat and forking cultivation) showed a small infestation (16%) of Ostrinia nubilalis while in the conventional variety on the second field (previous crop maize and not forking cultivation) the infestation of the European corn borer was almost three times higher (47%). In the conventional variety on both of the experimental fields we found a high Fusarium spp. infestation (70%). Especially species of the section Liseola dominates, among them: F. subglutinans, F. proliferatum und F. verticillioides. The Fusarium infestation in the samples of Bt-maize from the field with previous crop wheat and forking cultivation was just as high as in the conventional variety (70%). The infestation of Fusarium spp. in the samples of Bt-maize from the field with previous crop maize and forking cultivation was more than 20?% lower. 相似文献