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Avian influenza - diagnosis 总被引:1,自引:0,他引:1
Alexander DJ 《Zoonoses and public health》2008,55(1):16-23
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The commercial LCx amplification assay, usually employed to detect the Myocobacterium tuberculosis complex in respiratory specimens, was evaluated by comparing the results it gave with those obtained using Löwenstein-Jensen solid medium and pathological findings on 55 lymph nodes from cattle with positive and 10 lymph nodes from cattle with negative skin tests for tuberculosis. Fifty-three cultures (51 and 2, respectively) were positive for M. bovis, while the results for the LCx assay and the histological method were positive in 48 (45, 3) and 24 (20, 4) samples, respectively. None of the samples from cattle from certified tuberculosis-free herds were positive by any of the procedures. The results obtained with the LCx assay, compared with the culture procedure, regarded as the gold standard among the diagnostic techniques, gave a specificity of 91.6% and sensitivity of 90.5%. Although the sensitivity of LCx was suboptimal, DNA of M. bovis was detected in 81.8% of the skin test-positive animals. Amplification techniques could provide a rapid and reasonably reliable tool for detecting bovine tuberculosis. 相似文献
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《The Journal of Applied Poultry Research》2017,26(4):476-484
The aim of this study is to compare the hen-day egg production (HDEP) (%), egg size (ES) (g), feed intake (FI) (g), bodyweight (BWT) (kg), body weight gain (BWTG) (g), feed conversion ratio (FCR), feed utilization (FU), and mortality of imported and local commercial egg layers from one to 20 wk of lay, as well as to predict their egg sizes. Two-thousand-six-hundred Hy-line Silver Brown commercial layers (imported) and 2,470 Boschveld indigenous commercial layers (local) were reared from d old to 44 wk of age and fed the same diet throughout. ANOVA was used to test their effects due to the strains, and the CHAID algorithm of regression tree method was used to predict the ES. The local strain came into lay first at wk 20, while the imported came into lay at 21 wk of age. The imported layers performed better in ES, FI, HDEP, BWTG, and FCR (P < 0.05) throughout the laying period, while the local layers were better (P < 0.05) in BWT with higher mortality than the imported. Also, the imported layers performed better in FU (P < 0.05) at wk 4, 8, and 24. Among the imported, the highest ES (58.116 g) was obtained from chickens with HDEP of 13.266 < HDEP < 20.35 and FI of 137.95 < FI< 138.176, while in the local layers, the highest ES (54.802 g) was obtained from chickens with HDEP of 37.876 < HDEP < 47.802. 相似文献
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为了建立奶牛乳房炎大肠杆菌快速诊断与药敏试验方法,用刃天青钠取代大肠杆菌选择培养基MQQ中的酚红指示剂,通过对刃天青的工作浓度、大肠杆菌接种量和培养时间等参数的研究,建立了奶牛乳房炎大肠杆菌刃天青微量板快速诊断方法.将不同细菌及其感染模拟奶样进行刃天青微量板快速培养结果显示,此刃天青微量板对大肠杆菌具有很强的选择培养特性,能在10 h内获得明确诊断结果,并能反映奶牛乳腺大肠杆菌感染强度.对89份临床奶样进行大肠杆菌刃天青微量板快速诊断敏感性和特异性检测,结果显示,此刃天青微量板法诊断大肠杆菌阳性奶样敏感性高达100%,诊断大肠杆菌阴性奶样特异性高达94.9%,总符合率高达95.5%.在此基础上用矫正浓度10种抗生素包被微量板,分别用10株大肠杆菌纯培养菌株及其感染模拟奶样和10份大肠杆菌阳性奶样进行快速药敏试验,所获结果与标准纸片扩散法完全一致.这些研究结果表明,本研究建立的刃天青微量板法可以取代常规方法用于奶样大肠杆菌的快速诊断及药敏试验. 相似文献
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