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71.
72.
Yi-Suk Joo Soo-hwan An Ok-Kyung Kim Juan Lubroth Jung-Hyang Sur 《Canadian journal of veterinary research》2002,66(2):122-124
On March 20, 2000, a suspected vesicular disease in cattle was reported to the National Veterinary Research and Quarantine Service (NVRQS) of the Republic of Korea. This represented the index case of a foot-and-mouth disease (FMD) outbreak, which spread through several provinces. The Republic of Korea had been free of FMD for 66 years prior to the reintroduction of the virus and had recently suspended imports of pork and pork products from neighboring Japan owing to a reported FMD outbreak in that country. The Korean outbreak was ultimately controlled through the combination of preemptive slaughter, animal movement restrictions, and a strategy of ring vaccination. The purpose of this paper is to review the current FMD situation in Korea in the aftermath of its 2000 epizootic and how it may affect future efforts to eradicate or reduce risk of reintroduction of the disease into Korea. 相似文献
73.
β-葡聚糖对肉仔鸡生产性能及免疫功能的影响 总被引:6,自引:0,他引:6
选用1日龄AA肉仔鸡480只(公雏),随机分为5个处理组。每个处理6个重复,对照组饲喂基础日粮,抗生素组饲喂基础日粮 林可霉素,三个β-葡聚糖组,在基础日粮中分别添加25、50、100mg/kgβ-葡聚糖,以研究添加β-葡聚糖对肉鸡生产性能、免疫器官、细胞和体液免疫、血清中溶菌酶含量以及盲肠内乳酸杆菌的影响。结果显示:肉仔鸡日粮中添加50mg/kgβ-葡聚糖,显著提高0~49日龄日增重和饲料转化效率(P<0.05);显著提高21日龄脾脏的相对重量(P<0.05);添加β-葡聚糖有提高非特异性免疫力的趋势。 相似文献
74.
75.
Immunohistochemical detection of scrapie prion proteins in clinically normal sheep in Pennsylvania. 总被引:2,自引:0,他引:2
H Kim K I O'Rourke M Walter H G Purchase J Enck T K Shin 《Journal of veterinary diagnostic investigation》2001,13(1):89-91
Following diagnosis of scrapie in a clinically suspect Suffolk sheep, 7 clinically normal flockmates were purchased by the Pennsylvania Department of Agriculture to determine their scrapie status using an immunohistochemical procedure. Two of the 7 euthanized healthy sheep had positive immunohistochemical staining of the prion protein of scrapie (PrP-Sc) in their brains, nictitating membranes, and tonsils. The PrP-Sc was localized in the areas of the brain where, histopathologically, there was neurodegeneration and astrocytosis. The PrP-Sc occurred within germinal centers of the affected nictitating membranes and tonsils and was located in the cytoplasm of the dendrite-like cells, lymphoid cells, and macrophages. These results confirm that immunohistochemical examination of the nictitating membrane can be used as a screen for the presence of scrapie infection in clinically normal sheep at a capable veterinary diagnostic laboratory. In sheep with a PrP-Sc-positive nictitating membrane, the diagnosis of scrapie should be confirmed by histopathology and immunohistochemical examination of the brain following necropsy. Following full validation, immunohistochemistry assays for detection of PrP-Sc in nictitating membrane lymphoid tissues can improve the effectiveness of the scrapie control and eradication program by allowing diagnosis of the disease in sheep before the appearance of clinical signs. 相似文献
76.
农户舍饲奶牛血清钙及游离羟脯氨酸水平测定 总被引:2,自引:0,他引:2
采用氯胺T比色法和EDTANa_2滴定法,对重庆市农户舍饲奶牛不同泌乳阶段血清中游离羟脯氨酸与血清钙的水平进行 测定,旨在调查试验条件下奶牛血钙代谢情况以及骨营养不良发生的可能性。结果显示: 在农户全舍饲条件下,血清钙含量Ⅱ组显著低于Ⅴ组、Ⅵ组,其它各组间差异不显著;Ⅰ~ Ⅵ组血清羟脯氨酸含量分别为2.32±0.37μg/ml、2.36±0.59μg/ml、2.02±0.54μg/ml、1.90±0.44μg/ml、1.98±0.45μg/ml、1.79±0.18μg/ml,Ⅰ、Ⅱ组与Ⅵ组差异极显著。采样后2-3个月内进行临床观察,血清游离羟脯氨酸水平与骨营养不良发生率呈现一致性变化。而钙磷摄入不足,比例不当是主要原因。 相似文献
77.
陶为群 《安徽农业大学学报》2003,(5):78-80,90
由评委评分确定受评者的成绩,是一种普遍方式,但其中各个评委的作用识别问题却被忽视,因而无法确切地评价所选择的评委是否都很称职。本文提出根据受评者得分的总体结果,建立识别各评委作用的反馈控制,以提高选择评委的质量。因此构造了识别各评
委作用的二次规划数学模型,既适用于简单计算平均分作为受评者得分的评分模式,又适用于剔除高低分后再计算得分的评分模式,在普遍情形下得出唯一的求解结果。并且针对模型的特殊数据结构,给出了用最小二乘法求解的显式简便计算式,可以方便求解。进而使用这一方法,作了两个具体实例分析。 相似文献
78.
棉花冠层对不同灌水量的反应及其产量形成研究 总被引:1,自引:0,他引:1
通过探讨新疆北部棉区推广棉种新陆早6号与新陆早8号,在不同灌水量条件下冠层结构特征的差异性,得出新陆早6号对限量滴灌反应不敏感,而新陆早8号对限量滴灌反应较敏感。因此,在限量滴灌条件下,选择新陆早6号种植较适宜。叶面积指数低,叶片平均倾斜角度大,群体散射辐射透过系数和群体直射辐射透过系数增加,光能的截获率降低,由此得出,不同品种对灌水量的反应表现及理想群体冠层结构的合理指标,为增加棉花产量和提高水分利用效率提供了理论依据。 相似文献
79.
针对可编程控制器实践教学中存在的问题,研究制作符合实际教学特点的实验箱,从而在课程实验、课程设计、毕业设计、学生科技创新以及科学研究等方面发挥作用.可编程控制器实验箱主要进行了电源部分、输入端子、输出端子、实验面板及箱体的设计,在实际应用取得了较好的效果. 相似文献
80.
Stillborn and mummified swine fetuses from swine farms experiencing reproductive problems were investigated for evidence of infection with encephalomyocarditis (EMC) virus by fetal serology, virus isolation, and histopathologic examination. Fetal sera or thoracic fluids of 478 abnormal fetuses collected during January through December 1987 were tested for the presence of antibody specific to EMC virus. Of 478 samples tested, 175 (36.6%) had EMC virus serum neutralizing antibody titers of 1:64 or greater. The samples positive for EMC virus antibody were obtained from 38 swine farms located in 9 states in the United States. In addition to serologic observations, tissue samples of some abnormal fetuses were examined for the presence of virus and histopathologic lesions. The EMC virus was isolated in 1 case from the fetuses of an aborted litter. The isolate was serologically identical to a reference EMC virus. Nonsuppurative encephalitis and myocarditis were observed in the fetal samples collected from 2 different herds. Thoracic fluid of 1 stillborn pig with lesions was positive for EMC virus antibody at a titer of 1:512. We suggest that a widespread reproductive problem recently experienced in several major swine-producing areas of the United States may have been caused by EMC virus infection. 相似文献