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目的为开发中药防治畜禽沙门氏菌病,根据沙门氏菌病中兽医辩证进行中药组方,为今后畜禽养殖减抗限抗的替代疗法提供参考。方法采用倍比稀释法检测复方板蓝根口服液对鸡白痢沙门氏菌的最小抑菌质量浓度(minimum inhibitory concentration,MIC)和最小杀菌质量浓度(minimum bactericidal concentration,MBC),扫描电镜观察菌体形态变化。试验选取150羽1日龄雏鸡,随机取出30羽做空白组,其余120羽人工感染鸡白痢沙门氏菌,制备雏鸡感染模型。将感染雏鸡随机分为模型组、中药治疗组、西药治疗组和中药预防组,每组30羽。观察雏鸡的发病率及死亡率。于治疗后1、3和5 d检测血清中IL-1β和TNF-α的含量;实时荧光PCR检测禽β-防御素6 (avian beta-defensin 6,AvBD6) 和鸡Toll样受体15 (chicken toll-like receptor 15,ChTLR15) 在雏鸡小肠中的转录水平。结果体外试验结果显示:MIC和MBC分别为62.5和125 mg/mL;扫描电镜下可见菌体出现溢缩,断裂形成许多残体,形状不规则。中药预防组可降低雏鸡的发病率及死亡率。与模型组相比,中药预防组和中药治疗组均可降低IL-1β和TNF-α含量。而ChTLR15和AvBD6在感染初期表达量高,治疗后期趋于正常。结论复方板蓝根口服液对鸡白痢沙门氏菌有明显的抑制作用,其杀菌机制是通过改变菌体的形态结构使细菌丧失活性。试验证实复方板蓝根口服液可有效预防雏鸡沙门氏菌感染,并能有效降低体内炎性因子水平,减轻炎症反应。  相似文献   
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Vaccine for the control of egg drop syndrome '76   总被引:1,自引:0,他引:1  
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Furazolidone induces a cardiotoxicosis when fed in toxic concentrations to newly hatched ducklings. This preliminary experiment was designed to determine if creatine kinase (CK) isoenzymic activities or other serum analytes would be useful as indicators of these cardiac alterations. Sera from 12 ducklings (six fed a control ration and six fed the control ration with 700 mg furazolidone added per kg of feed [700 ppm] for 28 days) were analyzed for CK isoenzymic activities, electrolytes, nitrogenous metabolites, hepatic enzymic activities, bilirubin, and glucose. Statistically significant differences between control and treated groups were detected for creatine kinase MB (CK-MB, cardiac muscle origin) isoenzymic activity and bilirubin, potassium, calcium, and total carbon dioxide concentrations. Differences other than CK-MB isoenzymic activity were generally explained by factors related to the toxicosis or sample handling. These findings suggest that CK-MB isoenzymic activity may be useful to detect and monitor the progress of cardiac injury in furazolidone toxicosis, thereby increasing the usefulness of this model of dilated cardiomyopathy. Our findings, analyzed on the Kodak Ektachem 700 Dry Chemistry Analyzer, are compared with serum chemistry values reported in the literature.  相似文献   
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养殖家畜的冠状病毒,如猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV),其基因序列与蝙蝠体内冠状病毒基因序列高度相似,可引起猪肠道感染并导致仔猪大量死亡,对动物健康危害极大.本研究基于对美国猪群PEDV流行毒株表观流行率的数据挖掘作为先验信息,以2019年美国生猪入境中国西南...  相似文献   
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Examination of two collections of Donax serra from a South African west coast beach revealed the presence of Ciliophora, Trematoda, Nematoda and a parasitic pycnogonid. This is the first record of a pycnogonid from the genus Donax and the first published report of such a parasite from any southern African bivalve mollusc. One of the two trematode species found is described as new and its epidemiology is discussed briefly. No epibiota were found on the bivalve shell.  相似文献   
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There have been very few clinical trials evaluating therapies for naturally occurring spinal cord injury in dogs and cats. This review describes the methods suitable for evaluating the behavioural recovery of animals with spinal cord injuries, in either a clinical or a laboratory setting. A list of commonly used methods for evaluating behavioural recovery in animals is provided, both in the clinical and laboratory setting; the tests, their limitations and benefits and specific recommendations for their use are also discussed in more depth.  相似文献   
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BACKGROUND: Leukocytes appear to enter a hypo-inflammatory state in human patients with a severe bacterial infection, whereas, in swine, intra-abdominal sepsis produces an initial increase and subsequent decrease in neutrophil Fc receptor mediated phagocytosis. HYPOTHESIS: Impaired neutrophil function (hypo-inflammatory state) develops in dogs with sepsis. ANIMALS: Thirteen adult client-owned dogs that developed clinical signs consistent with sepsis were assessed for evidence of neutrophil dysfunction. These results were compared with those of 12 healthy dogs. METHODS: Flow cytometry combined with the appropriate fluorescent markers allowed for quantification of the phagolysosomal oxidative burst after Fc receptor-mediated phagocytosis of immune complexes, neutrophil phagocytosis of opsonized Escherichia coli, and the intracellular concentration of reduced glutathione as a measure of oxidative stress. RESULTS: The phagolysosomal oxidative burst after Fc receptor-mediated phagocytosis was significantly lower in neutrophils from septic dogs (mean fluorescence intensity +/- standard deviation; 118 +/- 13 and 165 +/- 27 for septic and control dogs, respectively, p = 0.001), although the phagocytosis of opsonized E. coli was significantly increased (155 +/- 74 and 77 +/- 44 for septic and control dogs, respectively, p = 0.004). Intracellular reduced glutathione was not significantly different in neutrophils from septic and healthy control dogs. CONCLUSIONS: An important component of neutrophil function is decreased in septic dogs. The diminished oxidative burst after Fc receptor-mediated phagocytosis in neutrophils from septic dogs could hinder the ability of the innate immune system to clear bacterial infections or it might help protect these patients from the systemic consequences of infection.  相似文献   
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