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991.
Five horses with a primary surgical lesion of the small (descending) colon were diagnosed with eosinophilic colitis based on visual and histopathological examination. These were evident as visibly striking, hyperaemic, focal lesions of the small colon, with serosal petechiation, oedema and marked thickening of the intestinal wall at the site. Areas of focal necrosis were also evident. The gross appearance of the lesions were considered to be sufficiently severe in all cases to merit resection, due to concerns about intestinal necrosis and septic peritonitis. An inability to fully exteriorise the affected portion of intestine to perform a resection and anastomosis necessitated intraoperative euthanasia of one horse. A total of three horses survived to hospital discharge. Eosinophilic colitis lesions are a rare cause of severe small colon disease, but should be considered in cases with similar visual characteristics. 相似文献
992.
An experiment was conducted to scientifically identify the appropriate feed for Gansu Alpine Fine Wool ewes in order to change the animals' breeding mode, which currently can only be mated at the age of 2.5 years due to insufficient nutritional supply. The experiment selected 48 12-month-old ewes and randomly divided them into group a (Diet 1), group b (Diet 2), group c (Diet 3), and a control group with no supplementary feeding. The feed test was run for 90 days. The rumen pH of groups a and b were very significantly higher (P<0.01) or group c significantly lower (P<0.05) than control group. The rumen ammonia nitrogen, protein nitrogen and total nitrogen of groups a, b and c were all higher than control group (P<0.01). The total volatile fatty acids of group a and b were all higher than the control group (P<0.01), group b significantly higher than group c (P<0.05). The molar ratio of acetic acid and propionic acid in group a was very significantly higher than control group (P<0.01), group b and c were significantly higher than control group (P<0.05). The molar ratio of butyric acid in group a was very significantly higher than group c (P<0.01). The ratio of acetic acid and propionic acid in group b was significantly lower than control group (P<0.05). The number of several rumen fiber-degrading bacteria and protozoa in groups a, b and c were very significantly (P<0.01) or significantly (P<0.05) higher than the control. In conclusion, this study shows that supplementary feeding can positively affect the rumen metabolic parameters and the number of several rumen microorganisms in Gansu Alpine Fine Wool ewes. In general, the effects of Diet 1 were the strongest, while Diet 2 also produced notable improvements. © 2018, Editorial Office of Acta Prataculturae Sinica. All rights reserved. 相似文献
993.
Latin-American cities can be characterized by dynamic processes of urbanization that encroach upon the natural and semi-natural surrounding landscapes. Our study presents the effects of landscape development, transformed from semi-natural conditions into a mostly disperse suburban settlement. We explore the impact that this transformation has had on this context by three ecosystem services that regulate rainwater runoff, enhance microclimate conditions and help to improve air quality by monitoring vegetation cover. We have designed a spatio-temporal hierarchical analysis which employs remote sensing techniques to capture the structural changes of this landscape over long, medium and short term scales on two spatial levels. This methodological approach was tested in the Metropolitan Area of Santiago (MAS) as case study area. Despite of the increase in impervious surfaces due to urban processes, there has also been an increase in vegetation cover, which has led to an improvement in the provision of the above-mentioned ecosystem services. Hence, if diverse urbanization processes continue and they are coupled with an increase in vegetation cover, the provision of ecosystem services could also expand. This phenomenon can be observed in some areas, where public and private green spaces are created and maintained. Our data analyses give evidence that certain types of suburban areas which increase the share of vegetation cover can provide daily ecological benefits for urban neighborhoods, and beyond, for adjacent areas. Moreover, suburban development can successfully provide ecological benefits to citizens. Such processes can only be ecologically sustainable if the composition of vegetation is well-adapted to the regional climatic conditions. 相似文献
994.
为了有效防控云南布朗山区木薯重要地下害虫的发生与危害,本试验针对性地开展种茎无害化药剂处理的防效评价研究。结果表明:选用环保型杀虫剂48%乐斯本乳油1 000倍液和1.8%阿维菌素乳油2 000倍液的1∶1混合液浸泡木薯种茎5和10 min后种植效果最好,平均出苗率分别由无任何处理对照的62.5%及清水对照的75.0%和75.6%显著提高到96.5%和97.0%,平均虫害率分别由无任何处理对照的56.8%及清水对照的45.0%和44.8%显著下降到6.3%和5.5%,平均产量分别由无任何处理对照的1 11 相似文献
995.
随着社会经济的发展,人们对户外登山健身的需求日益迫切。近年来,宁波市登山健身步道建设发展迅速,登山健身步道长度和登山游客规模快速增长,"步道经济"初步形成。为了适应宁波市登山健身步道建设发展的需要,该文在全面调查全市登山步道空间分布、沿线自然景观、游客规模及其需求的基础上,针对如何更好的利用宁波市优越的自然、历史、人文资源,从步道空间布局、自然和历史文化特色、基础设施建设、步道沿线自然景观优化等方面,对全市登山健身步道建设进行了初步探索,以期为其建设提供有价值的参考意见和建议。 相似文献
996.
Estimating future fluxes of CH4 between land and atmosphere requires well-conceived process-based biogeochemical models. Current models do not represent the anaerobic oxidation of methane (AOM) in land surface soils, in spite of increasing evidence that this process is widespread. Our objective was to determine whether AOM, or potential AOM, commonly occurs in 20 hydromorphic soils spanning a wide range of chemical properties. Bulk soil samples were collected under shallow water near the shoreline of 15 recently drained fish ponds in southern Bohemia (Czech Republic), as well as from below the water table at 3 peatland locations in northeast Scotland and 2 acid sulfate soils on the southern coast of Finland. Each soil slurry was incubated under both oxic and anoxic conditions, with or without the addition of alternative electron acceptors (SO42− and NO3−) or H2PO4−. Here, “oxic” and “anoxic” conditions refer to anoxic soil respectively incubated in a headspace containing air or argon. Using the isotope dilution method, we determined the gross production and oxidation rates of CH4 after 2 days incubation under oxic headspace conditions, and after 2, 21 and 60 days incubation under anoxic conditions. Large differences in net CH4 fluxes were observed between soil types and between incubation conditions. AOM was detected in each of the 20 bulk soil samples, which spanned >6 pH units and 2 orders of magnitude in organic C content. Significant positive relationships were found between AOM and gross CH4 production rates under anoxic conditions, resulting in AOM rates that were sometimes higher than CH4 oxidation rates under oxic headspace conditions. There was no relationship between net and gross CH4 production rates, such that 2 soil types could display similar low net rates, yet conceal very large differences in gross rates. The effects of alternative electron acceptors on AOM were idiosyncratic and resulted in no net trend. We did find, however, a negative effect of SO42− and H2PO4− on gross CH4 production rates under anoxic and oxic conditions respectively. Under oxic headspace conditions, CH4 oxidation was related to soil organic C content. Taken collectively, our results suggest that AOM, or potential AOM, is prevalent over a wide range of soil types, that AOM may contribute substantially to CH4 oxidation in soils, and that AOM in soils should be integrated to current process-based CH4 cycling models. 相似文献
997.
不同温度下圆叶决明降解过程红壤可溶性氮及氮水解酶动态变化研究 总被引:1,自引:0,他引:1
为了探明圆叶决明(Chamaecrista rotundifolia)降解过程果园红壤供氮水平的变化规律,本研究采用模拟培养试验,研究15℃和25℃培养果园红壤硝态氮、铵态氮、可溶性总氮、可溶性有机氮含量的变化及脲酶、蛋白酶、天冬酰胺酶活性的变化。结果表明,圆叶决明降解过程果园红壤4种可溶性氮含量均显著提高,且在培养140 d达到最大值,25℃培养的效果更佳。其中,可溶性总氮、可溶性有机氮和硝态氮含量随时间的动态变化可用三次曲线方程来拟合。圆叶决明降解过程还能显著提高脲酶、蛋白酶和天冬酰胺酶的活性,其中蛋白酶活性和脲酶活性的变化可用指数方程和三次曲线方程来拟合。本研究认为圆叶决明降解过程可提高果园红壤可溶性氮含量,因此可通过翻压圆叶决明提高土壤的供氮水平。 相似文献
998.
Ecological ravages, environmental pollution, and the developmental problems of regional ecology, economy, and society are not geographical restrictions. The synergistic development of the ecology-economy-society system in forestry was quantitatively assessed by system theory and synergistic dynamic models, illustration of the metering principle and corresponding theory, assessing and quantizing synergistic development status of ecology-economy-society system, and the orderliness of the subsystem of the last decade. The orderliness of the ecology and ecological subsystems developed unstably with an increasing trend. The eco-environment construction and eco-conservation achievement of forestry in China are effective and need to be maintained. The industry structure should be improved to promote the growth of the forestry economy. The society subsystem development is increasing but is not at a high level, which indicates that the public demand to ecological service was not satisfied. The theoretical analysis and numerical examples show that the development of the forestry system has a good development state. The synergy changes of forestry system in the 0 to 0.951 range, which is in the intermediate degree of synergy during this period. It still needs much improvement on efficiency of synergy. The orderliness and the relationship among the subsystems of forestry should be improved in future. 相似文献
999.
1000.