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121.
采用鸡杆菌自然病例分离纯化的鸡杆菌人工感染开产前(105日龄)和开产后(163日龄)的SPF蛋鸡,运用组织学的方法对鸡杆菌自然病例和试验病例进行比较病理学观察。结果表明,自然病例和试验病例均可引起蛋鸡产蛋高峰推迟,产蛋量下降,且多产畸形蛋;病变主要在呼吸道和生殖道,主要表现为呼吸道和生殖道黏膜层严重充血、水肿、浆液性及炎性渗出等反应。但是试验病例未出现自然病例中常见的腹膜炎和输卵管炎症状。输卵管的病变主要在膨大部和子宫部,这种特征性病变可作为该病病理诊断的重要指征之一。这表明鸡杆菌单因子感染可引起SPF开产蛋鸡生产性能明显降低以及呼吸道和生殖道的病理变化。 相似文献
122.
Background
In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals.Methods
A Faecal Egg Count Reduction Test (FECRT) was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming and 14 days later. Faecal Egg Count Reductions (FECRs) were calculated on arithmetic means of transformed individual FECRs and on arithmetic means of individual FECRs.Results
Seventy-nine (48%) out of a total of 165 foals sampled were positive for P. equorum eggs before deworming and 66 of these met the criteria for being used in the efficacy assessment. It was shown that there was no, or very low activity of ivermectin on the output of ascarid eggs in the majority of the foals, whereas for fenbendazole and pyrantel it was >90%.Conclusion
Ivermectin resistance was shown in 5 out of 6 farms. Therefore, ivermectin should not be the drug of choice in the control of P. equorum infections in foals. According to the results of this study, fenbendazole or pyrantel are still effective and should be used against this parasite. 相似文献123.
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125.
较为系统地阐述了二十世纪后二十年祁连县畜牧业的现状及主要制约畜牧业发展的因素 ,有针对性的提出了较为合理的发展思路、对策及应采取的措施 ,并提出要想使祁连县畜牧业加快发展 ,首先要对现有畜牧业结构进行战略性调整 ,加大推进畜牧业产业化经营 ,综合治理草地生态环境 ,强化牧业基础设施建设 ;其次是加快畜牧业科技进步 ,实施种子工程 ,搞好畜疫防治 ;另外 ,加强领导、转变工作作风也是加快畜牧业发展的重要措施之一。 相似文献
126.
Detection of canine microalbuminuria using semiquantitative test strips designed for use with human urine 总被引:6,自引:0,他引:6
Pressler BM Vaden SL Jensen WA Simpson D 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2002,31(2):56-60
Background — Commercial testing for microalbuminuria in human urine is often performed with point-of-care semiquantitative test strips followed by quantitative testing when indicated. An ELISA that quantifies canine urine albumin concentration has been developed, but semiquantitative test strips for use in the dog are not available.
Objective — The purpose of this study was to prospectively determine the concordance of canine urine albumin concentrations measured by a commercial human test strip and by ELISA.
Methods — Urine samples were obtained from 67 dogs evaluated for a variety of clinical conditions. Dipstick urinalyses were performed on all samples; clinician discretion determined method of urine collection and performance of urine sediment examination and/or urine culture. Urine albumin concentration was determined using test strips (Clinitek Microalbumin, Bayer Corporation, Elkhart, Ind, USA), and results were compared with those obtained by ELISA.
Results — The Clinitek strips correctly determined albumin concentration in 42 of 67 (63%) urine samples tested. Concordance was lowest (48%) for dogs with microalbuminuria (10–300 μg/mL by ELISA). Clinitek strip sensitivity and specificity for correct identification of microalbuminuria were 48% and 75%, respectively. Concordance was lower in dogs with urinary tract infection or hematuria and in samples collected by catheterization. Sensitivity and specificity for correct identification of microalbuminuria after exclusion of dogs with urinary tract infection or hematuria were 59% and 83%, respectively.
Conclusion — These results suggest that the Clinitek strips lack sufficient concordance with results obtained by ELISA to be reliable screening tests for microalbuminuria in the dog. A reliable semiquantitative point-of-care test for canine urine albumin concentrations below those detected by standard urine dipsticks is still needed. 相似文献
Objective — The purpose of this study was to prospectively determine the concordance of canine urine albumin concentrations measured by a commercial human test strip and by ELISA.
Methods — Urine samples were obtained from 67 dogs evaluated for a variety of clinical conditions. Dipstick urinalyses were performed on all samples; clinician discretion determined method of urine collection and performance of urine sediment examination and/or urine culture. Urine albumin concentration was determined using test strips (Clinitek Microalbumin, Bayer Corporation, Elkhart, Ind, USA), and results were compared with those obtained by ELISA.
Results — The Clinitek strips correctly determined albumin concentration in 42 of 67 (63%) urine samples tested. Concordance was lowest (48%) for dogs with microalbuminuria (10–300 μg/mL by ELISA). Clinitek strip sensitivity and specificity for correct identification of microalbuminuria were 48% and 75%, respectively. Concordance was lower in dogs with urinary tract infection or hematuria and in samples collected by catheterization. Sensitivity and specificity for correct identification of microalbuminuria after exclusion of dogs with urinary tract infection or hematuria were 59% and 83%, respectively.
Conclusion — These results suggest that the Clinitek strips lack sufficient concordance with results obtained by ELISA to be reliable screening tests for microalbuminuria in the dog. A reliable semiquantitative point-of-care test for canine urine albumin concentrations below those detected by standard urine dipsticks is still needed. 相似文献
127.
128.
为研究细胞信号转导和骨架在人源福氏志贺菌侵袭鸡肠上皮原代细胞中的作用,分别用酪氨酸蛋白激酶、酪氨酸蛋白磷酸酶、蛋白激酶C、Ca2+通道等信号转导抑制剂染料木黄酮、原钒酸钠、星状孢子素、硝苯地平和微丝蛋白聚合抑制剂细胞松弛素B处理鸡肠上皮原代细胞后,采用细胞免疫组织化学染色检测人源福氏志贺菌ZD02株对鸡肠上皮原代细胞侵袭率,用间接免疫荧光双重标记检测ZD02株侵袭鸡肠上皮原代细胞后F-肌动蛋白分布的变化。结果显示,染料木黄酮、硝苯地平和细胞松弛素B能显著抑制人源福氏志贺菌ZD02株内化,星状孢子素和原钒酸钠对ZD02株的内化无影响,人源福氏志贺菌侵袭鸡肠上皮原代细胞时F-肌动蛋白发生聚集。本研究表明人源福氏志贺菌ZD02株侵袭鸡肠上皮原代细胞过程中需要酪氨酸蛋白激酶、Ca2+通道活化以及细胞微丝重排。 相似文献
129.
对内蒙古阿拉善左旗红砂荒漠土壤盐分离子含量和土壤含水量的分布规律进行了研究,并对两者之间做了相关和回归分析。结果表明,阿拉善左旗红砂荒漠土壤中盐分离子的含量,阳离子以Na+为主,阴离子以SO42-为主。在垂直分布上,Mg2+、Na+、Cl-和SO42-含量随着土层深度的增加而增加,而K+、CO32-和HCO3-含量随着土层深度的增加而减少。阿拉善左旗3个地区(乌力吉、长流水和孪井滩)的土壤含水量介于1.39%~8.01%之间,平均含水量为5.02%。3个地区中,红砂荒漠土壤所含盐分离子中的Mg2+、Cl-和SO42-均与其土壤含水量之间存在明显的线性关系。 相似文献
130.