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Forty 11- to 13-month-old Friesian calves were inoculated with live Babesia bovis vaccine. Twenty of the calves were treated with long acting oxytetracycline seven and 15 days after receiving the vaccine. Parasites were detected in nine of the treated calves compared with all 20 of the untreated control group. Treated calves were less febrile and had higher packed cell volumes than control animals. All calves from both groups developed a considerable antibody titre to B bovis. It appears that long acting oxytetracycline can mitigate the response of sensitive cattle breeds to live antibabesial vaccine and prevent damage caused by excessive multiplication of B bovis parasites.  相似文献   
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Land–water interactions were examined in three regions in the Virginian Biogeographic Province; the southern shore of Cape Cod, Massachusetts; the Hudson/Raritan region of New York; and the eastern shore of the Delmarva (Delaware/Maryland/Virginia) Peninsula. Cumulative distribution functions were used to evaluate similarity in environmental condition among estuaries. Spatial-setting variables (location in a river, coastal lagoon, or in open waters) were associated with variation for some measures of estuarine condition. Patterns of coastal urban and agriculture gradients were measured and their relationship with indicators of estuarine condition was modeled statistically. When estuaries were pooled, the highest variation explained by spatial-setting variables was found for dissolved oxygen (DO, R 2 = 0.44) and salinity (R 2 = 0.58), with DO decreasing in river locations and salinity decreasing with rainfall and sampling locations near rivers. The explanatory power for the other indicator variables was low and varied from 6% to 27%. Rainfall explained some of the variation (R 2 = 0.23) in total suspended solids. Moderate (0.4 < | r | < 0.7) to strong (| r | ≥ 0.7) linear associations were found between total urban area and measures of estuarine condition. Within regions, total urban area was positively associated with Silver (r = 0.59), Cadmium (r = 0.65), and Mercury (r = 0.47) in Cape Cod, and inversely related to DO (r = −0.65) in the Hudson/Raritan region. No associations were found in the Delmarva Peninsula study area. Total area of agriculture showed a moderate association with Arsenic in Cape Cod, but no other associations were found in the other two regions. Our analyses show a measurable impact of urban land use on coastal ecosystem condition over large areas of the northeastern United States. This pattern was most evident when many different landscapes were considered simultaneously. The relationship between urban development and estuarine condition were weaker within the individual regions studied. The use of land use/cover models for predicting estuarine condition is a challenging task that warrants enhancements in the type, quantity, and quality of data to improve our ability to discern relationships between anthropogenic activities on land and the condition of coastal environments.  相似文献   
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Our main goal was to investigate if robust chemical fingerprints could be developed for three Argentinean red wines based on organic, inorganic, and isotopic patterns, in relation to the regional soil composition. Soils and wines from three regions (Mendoza, San Juan, and Co?rdoba) and three varieties (Cabernet Sauvignon, Malbec, and Syrah) were collected. The phenolic profile was determined by HPLC-MS/MS and multielemental composition by ICP-MS; (87)Sr/(86)Sr and δ(13)C were determined by TIMS and IRMS, respectively. Chemometrics allowed robust differentiation between regions, wine varieties, and the same variety from different regions. Among phenolic compounds, resveratrol concentration was the most useful marker for wine differentiation, whereas Mg, K/Rb, Ca/Sr, and (87)Sr/(86)Sr were the main inorganic and isotopic parameters selected. Generalized Procrustes analysis (GPA) using two studied matrices (wine and soil) shows consensus between them and clear differences between studied areas. Finally, we applied a canonical correlation analysis, demonstrating significant correlation (r = 0.99; p < 0.001) between soil and wine composition. To our knowledge this is the first report combining independent variables, constructing a fingerprint including elemental composition, isotopic, and polyphenol patterns to differentiate wines, matching part of this fingerprint with the soil provenance.  相似文献   
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当前兽药地方标准清理工作已进入攻关阶段,但在清理地方标准的实际工作中尚存在一些问题,笔者分析了这些具体问题,认为在升标工作中,政府应当给予合理的政策扶持,加快地方标准清理工作进度,保护企业利益;企业应当着重做好品种筛选,合理安排临床试验资金投入;企业通过采取联合参与升标方式,减少资金投入;对于移植外省标准,可采取不同措施妥善解决;为保证升标工作顺利进行,农业部和各省兽医行政管理部门应做好升标培训指导工作.  相似文献   
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Episodes of nonvolcanic tremor and accompanying slow slip recently have been observed in the subduction zones of Japan and Cascadia. In Cascadia, such episodes typically last a few weeks and differ from "normal" earthquakes in their source location and moment-duration scaling. The three most recent episodes in the Puget Sound/southern Vancouver Island portion of the Cascadia subduction zone were exceptionally well recorded. In each episode, we saw clear pulsing of tremor activity with periods of 12.4 and 24 to 25 hours, the same as the principal lunar and lunisolar tides. This indicates that the small stresses associated with the solid-earth and ocean tides influence the genesis of tremor much more effectively than they do the genesis of normal earthquakes. Because the lithostatic stresses are 10(5) times larger than those associated with the tides, we argue that tremor occurs on very weak faults.  相似文献   
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Feather loss in psittacine birds is an extremely common and extremely frustrating clinical presentation. Causes include medical and non-medical causes of feather loss both with and without overt feather destructive behavior. Underlying causes are myriad and include inappropriate husbandry and housing; parasitic, viral and bacterial infections; metabolic and allergic diseases; and behavioral disorders. Prior to a diagnosis of a behavioral disorder, medical causes of feather loss must be excluded through a complete medical work-up including a comprehensive history, physical exam, and diagnostic testing as indicated by the history, signalment and clinical signs. This article focuses on some of the more common medical and non-medical causes of feather loss and feather destructive behavior as well as approaches to diagnosis and treatment.  相似文献   
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当前兽药生产企业已全面通过GMP验收,兽药科技创新成为后GMP时代企业生存发展的首要任务。在此形势下江苏省提出了“建设兽药强省”工作思路。针对当前江苏乃至全国兽药产业现状进行了调查分析和研究探索,就如何充分利用本省科研优势和GMP建设形成的基础设施优势,在政府投入引导机制、合作创新开发机制和企业内研发机制等方面提出了建设性意见。  相似文献   
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