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101.
We observed a significant difference in the organic acid profile of diarrheal feces between pigs infected with and free from pathogenic spirochetes. Diarrhea and loose feces were collected from growing pigs, held at 15 different commercial farms. A total of 106 samples were measured for organic acid concentration by HPLC and were checked for the presence of B. hyodysenteriae and B. pilosicoli by PCR. B. hyodysenteriae was detected in 3 samples collected from one farm. B. pilosicoli was detected in 5 samples collected from another farm. Lower concentrations of iso-butyrate and iso-valerate were likely associated with development of pathogenic spirochete infection.  相似文献   
102.
The purpose of this study was to determine the serological and molecular prevalence of Bartonella spp. infection in a sick dog population from Brazil. At the S?o Paulo State University Veterinary Teaching Hospital in Botucatu, 198 consecutive dogs with clinicopathological abnormalities consistent with tick-borne infections were sampled. Antibodies to Bartonella henselae and Bartonella vinsonii subsp. berkhoffii were detected in 2.0% (4/197) and 1.5% (3/197) of the dogs, respectively. Using 16S-23S rRNA intergenic transcribed spacer (ITS) primers, Bartonella DNA was amplified from only 1/198 blood samples. Bartonella seroreactive and/or PCR positive blood samples (n=8) were inoculated into a liquid pre-enrichment growth medium (BAPGM) and subsequently sub-inoculated onto BAPGM/blood-agar plates. PCR targeting the ITS region, pap31 and rpoB genes amplified B. henselae from the blood and/or isolates of the PCR positive dog (ITS: DQ346666; pap31 gene: DQ351240; rpoB: EF196806). B. henselae and B. vinsonii subsp. berkhoffii (pap31: DQ906160; rpoB: EF196805) co-infection was found in one of the B. vinsonii subsp. berkhoffii seroreactive dogs. We conclude that dogs in this study population were infrequently exposed to or infected with a Bartonella species. The B. henselae and B. vinsonii subsp. berkhoffii strains identified in this study are genetically similar to strains isolated from septicemic cats, dogs, coyotes and human beings from other parts of the world. To our knowledge, these isolates provide the first Brazilian DNA sequences from these Bartonella species and the first evidence of Bartonella co-infection in dogs.  相似文献   
103.
The dynamics of blood neutrophil acyloxyacyl hydrolase (AOAH) activity, the appearance of endotoxin (lipopolysaccharide, LPS) in blood and the role of blood neutrophil AOAH in the severity of Escherichia coli and endotoxin mastitis were investigated in early postpartum dairy cows experimentally challenged with either endotoxin (n = 6) or E. coli (n = 6). The AOAH activity of blood neutrophils started to decrease significantly at post challenge hours (PCH) 6-24 and 12-24 in the endotoxin and E. coli-challenged groups, respectively; it returned to pre-challenged values at PCH 48 in both endotoxin- and E. coli-challenged groups. The cows were classified as moderate and severe responders according to milk production loss in the non-challenged quarters at PCH 48. There were no severe responders in the endotoxin-challenged group. In the E. coli-challenged group, only 1 severe responder was identified. The pre-challenge neutrophil AOAH activity of the severe responder was approximately 30% lower than that of moderate responders. No LPS was detected in the plasma of endotoxin-challenged cows; neither was it found in the plasma of moderate responders in the E. coli-challenged group at any PCH. However, at PCH 6, a remarkable amount of LPS was detected in the plasma of the severe responder from the E. coli-challenged group. Furthermore, neutrophil AOAH activity was increased by approximately 70% in the severe responder at PCH 6, but it increased by only approximately 15% in moderate responders. This was followed by a decreased neutrophil AOAH activity at PCH 12-24 and 24-72 in moderate and severe responders, respectively; the decreased AOAH activity at those PCH was more pronounced in the severe responder. The pronounced decreased neutrophil AOAH activity during mastitis often coincided with extreme leukopenia, neutropenia and a maximal number of immature neutrophils in the blood. Our results demonstrate that a decrease in neutrophil AOAH activity results in the appearance of LPS in the blood, and low blood neutrophil deacylation activity could be considered as a risk factor for severe clinical coliform mastitis.  相似文献   
104.
During the last decades, European red foxes (Vulpes vulpes) have been implicated in the transmission of several viral or parasitic pathogenic agents to domestic animals and humans. In urban areas, risks of zoonoses transmission are likely to increase as a result of a higher rate of intra- and inter-species contacts. Foxes occur on 35% of the Brussels-Capital Region area and local densities reach up to 4 family groups per square kilometre. According to the directive 2003/99/ECC, a first survey for the presence in foxes of Echinococcus multilocularis and Toxocara canis was conducted in Brussels from 2001 to 2004. None of 160 foxes were found to be infected with E. multilocularis and 24 of 134 foxes were found to be infected with T. canis. Considering numbers of examined foxes, the sensitivity and the specificity of tests used for diagnosis, the 95% credibility intervals for the true prevalence of E. multilocularis and T. canis were estimated in a Bayesian framework to be 0 to 1.87% (median value of 0%) and 12.7 to 26% (median value of 18.7%), respectively. For T. canis, a significantly higher risk to be a carrier occurs in cubs and a significantly lower risk in adults.  相似文献   
105.
OBJECTIVES: The aim of this study was to explore the attitudes of veterinarians and clients towards expressions of clinical uncertainty. METHODS: Questionnaires that assessed the respondent's attitudes towards expressions of clinical uncertainty were completed by clients at six small animal practices. In addition, questionnaires that evaluated what veterinarians thought their client's attitudes would be towards expressions of clinical uncertainty were completed by veterinarians. The responses from clients and veterinarians were statistically compared. RESULTS: Veterinarians significantly underestimated the desire of clients to be told about uncertainties in treatment and significantly overestimated how the expression of uncertainty would generally reduce client confidence. Veterinarians significantly overestimated the loss of client confidence resulting from saying "I am not sure about this" and from asking a nurse for advice. Both clients and veterinarians considered that verbal expressions of uncertainty would lead to a greater reduction in client confidence than behavioural expressions of uncertainty. CLINICAL SIGNIFICANCE: This study suggests that most clients want to be told about their veterinarian's clinical uncertainties, and how this uncertainty is expressed can markedly influence client confidence.  相似文献   
106.
This paper reports three clinical cases of needle tract implantation of neoplastic cells on the abdominal and thoracic wall after ultrasound (US) fine needle aspiration biopsy (FNAB). Primary tumors were two transitional cell carcinomas of the urinary bladder (2 dogs) and one pulmonary adenocarcinoma (1 cat). All three masses grew up along the needle tract. To our knowledge, the seeding of pulmonary adenocarcinoma cells after FNAB on the thoracic wall has never been reported in veterinary medicine.  相似文献   
107.
Journal of Plant Diseases and Protection - The host response of 17 cover crop cultivars to infection by single-species populations of Pratylenchus hippeastri, Pratylenchus vulnus and Pratylenchus...  相似文献   
108.
109.
本研究通过细胞融合、间接ELISA方法筛选出4株可稳定分泌犬瘟热病毒(canine distemper virus,CDV)和犬细小病毒(canine parvovirus,CPV)单克隆抗体的杂交瘤细胞株,以此为基础研制了一种可同时检测CDV和CPV的胶体金二联检测卡,并对其特异性、灵敏度及准确性进行了测试。结果显示:4株杂交瘤细胞可稳定传代,分泌的单克隆抗体纯度高,效价均在1:320以上。制备的胶体金二联检测卡特异性强,只与CDV和CPV产生特异性条带,而不与其他犬类病毒反应;灵敏度高,最低检测限可达到102拷贝/μL;准确性好,与荧光定量PCR结果的符合率高于88.0%,与市面上单一病毒检测卡的符合率高于97.2%。结果表明,本研究制备的CDV、CPV胶体金二联检测卡特异性强、灵敏度高、准确性好,兼具操作简便、肉眼可判读、结果易保存和无需特殊仪器设备等优势,可用于两种疾病的临床快速诊断和大规模检测工作。  相似文献   
110.
为评价各种误差对微操作器精度的影响,以一体化超精密微操作器为研究对象,分析了加工误差、机构原理误差、测量误差、环境带来的误差以及驱动误差等造成微操作器精度降低的因素,建立了加工误差的偏微分方程解析模型,并用有限元仿真验证了加工误差模型的准确性。在详细分析误差源的基础上,提出了提高微操作器精度的措施。  相似文献   
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