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991.
C.S. Mansfield F.E. James M. Craven D.R. Davies A.J. O'Hara P.K. Nicholls B. Dogan S.P. MacDonough K.W. Simpson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(5):964-969
Background: Historically, histiocytic ulcerative (HUC) (or granulomatous) colitis of Boxer dogs was considered an idiopathic immune-mediated disease with a poor prognosis. Recent reports of dramatic responses to enrofloxacin and the discovery of invasive Escherichia coli within the colonic mucosa of affected Boxer dogs support an infectious etiology.
Hypothesis: Invasive E. coli is associated with colonic inflammation in Boxer dogs with HUC, and eradication of intramucosal E. coli correlates with clinical and histologic remission.
Animals: Seven Boxer dogs with HUC.
Methods: Prospective case series. Colonic biopsies were obtained at initial evaluation in 7 dogs, and in 5 dogs after treatment with enrofloxacin. Biopsies were evaluated by standardized histopathology, and fluorescence in situ hybridization (FISH) with probes to eubacteria and E. coli .
Results: Intramucosal E. coli was present in colonic biopsies of 7/7 Boxers with HUC. Clinical response was noted in all dogs within 2 weeks of enrofloxacin (7±3.06 mg/kg q24 h, for 9.5±3.98 weeks) and was sustained in 6 dogs (median disease-free interval to date of 47 months, range 17–62). FISH was negative for E. coli in 4/5 dogs after enrofloxacin. E. coli resistant to enrofloxacin were present in the FISH-positive dog that relapsed.
Conclusions and Clinical Relevance: The correlation between clinical remission and the eradication of mucosally invasive E. coli during treatment with enrofloxacin supports the causal involvement of E. coli in the development of HUC in susceptible Boxer dogs. A poor response to enrofloxacin treatment might be due to colonization with enrofloxacin-resistant E. coli . 相似文献
Hypothesis: Invasive E. coli is associated with colonic inflammation in Boxer dogs with HUC, and eradication of intramucosal E. coli correlates with clinical and histologic remission.
Animals: Seven Boxer dogs with HUC.
Methods: Prospective case series. Colonic biopsies were obtained at initial evaluation in 7 dogs, and in 5 dogs after treatment with enrofloxacin. Biopsies were evaluated by standardized histopathology, and fluorescence in situ hybridization (FISH) with probes to eubacteria and E. coli .
Results: Intramucosal E. coli was present in colonic biopsies of 7/7 Boxers with HUC. Clinical response was noted in all dogs within 2 weeks of enrofloxacin (7±3.06 mg/kg q24 h, for 9.5±3.98 weeks) and was sustained in 6 dogs (median disease-free interval to date of 47 months, range 17–62). FISH was negative for E. coli in 4/5 dogs after enrofloxacin. E. coli resistant to enrofloxacin were present in the FISH-positive dog that relapsed.
Conclusions and Clinical Relevance: The correlation between clinical remission and the eradication of mucosally invasive E. coli during treatment with enrofloxacin supports the causal involvement of E. coli in the development of HUC in susceptible Boxer dogs. A poor response to enrofloxacin treatment might be due to colonization with enrofloxacin-resistant E. coli . 相似文献
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993.
Dorsal displacement of the soft palate is an important cause of poor performance in racehorses, yet its etiology is not fully understood. Diagnosis requires treadmill videoendoscopy, which is not widely available. The relationship of the larynx, the hyoid apparatus, and the remainder of the skull may be important in predisposing horses to dorsal displacement of the soft palate. We hypothesized that this relationship could be accurately assessed in unsedated horses through ultrasonographic examination. Fifty-six racehorses presented for evaluation of poor performance were subjected to treadmill videoendoscopy and resting ultrasonography. Using ultrasound-assisted percutaneous measures of laryngo-hyoid position, the relationship between selected anatomic structures and the occurrence of dorsal displacement of the soft palate was evaluated. A significant relationship was found between the depth of the basihyoid bone at rest and the occurrence of dorsal displacement of the soft palate at exercise ( P =0.03). Other measures of laryngohyoid position were not found to be associated with dorsal displacement of the soft palate. Thus, there is an association between the occurrence of dorsal displacement of the soft palate at exercise and the resting position of the basihyoid bone, whereby on average a more ventral location of the basihyoid bone is present in horses with dorsal displacement of the soft palate. The pathophysiologic implications of this finding are not fully understood but, based on our findings, ultrasound examination is of value in assisting in the diagnosis of dorsal displacement of the soft palate. 相似文献
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996.
2008年通过对张掖市平山湖蒙古族乡草地、农牧业生产经营情况的入户调查,全乡有天然草地8.67万hm^2,可利用草地6.38万hm^2。草地理论载畜量为2.03万羊单位,实际存栏6.843万羊单位,超载4.813万羊单位,达237%。由于草地严重超载过牧,造成温性荒漠草地退化加剧,裸露草地数量增加,水土流失严重,草原生态环境日益恶化,使当地农牧民生产、生活受到严重的影响。必须通过调整优化畜群结构,使饲养牲畜公母比例由1∶1.4提高到1∶2.5-3.0,改变传统的全放牧饲养方式,加快畜群周转,达到草畜平衡,实现草地畜牧业可持续发展。 相似文献
997.
用纯化的猪繁殖与呼吸综合征病毒(PRRSV)A06株病毒抗原免疫Balb/c小鼠,取免疫小鼠脾细胞与SP2/0骨髓瘤细胞进行细胞融合.经间接ELISA方法筛选,有限稀释法克隆,获得4株稳定分泌特异性单克隆抗体的杂交瘤细胞株,分别命名为3D12、4E10、6E2和7G6.其细胞培养上清效价分别为1:256、1:512、1:512和1:256,小鼠腹水效价分别为1:1.024×106、1:2.048×106、1:1.024×106和1:2.048×106.亚型鉴定表明,3D12、4E10、6E2和7G6分别为IgG2b、IgG2b、IgG1和IgG2a.ELISA检测结果显示,4种PRRSV单克隆抗体仅与PRRSV反应,不与其他病毒反应,表明均为抗PRRSV的型特异性单克隆抗体.对单克隆抗体腹水液进行IgG提取纯化,SDS-PAGE电泳验证,仅出现两条清晰条带,无杂带出现,证明纯化效果较好.这4种单克隆抗体的获得,为建立PRRSV检测方法提供了强有力的工具. 相似文献
998.
Ana Afonso Jose Cortinas Abrahantes Franz Conraths Anouk Veldhuis Armin Elbers Helen Roberts Yves Van der Stede Estelle Méroc Kristel Gache Jane Richardson 《Preventive veterinary medicine》2014
During the Schmallenberg virus (SBV) epidemic, the European Food Safety Authority (EFSA) collected data on SBV occurrence across Europe in order to provide an assessment of spread and impact. By May 2013, twenty-nine countries were reporting to EFSA and twenty-two countries had reported cases of SBV. The total number of SBV herds reported was 13,846 and the number of SBV laboratory confirmed herds was 8730. The surveillance activities were based on the detection of SBV clinical cases (either adults or newborns). Malformation in newborns was the most commonly reported clinical sign of SBV-infection. All countries were able to provide the date when the first suspicion of SBV in the herd was reported and nineteen could report the location of the herd at a regional level. This allowed the spread of SBV in Europe to be measured both temporally and spatially. The number of SBV confirmed herds started to increase in December 2011 and two peaks were observed in 2012 (February and May). Confirmed herds continued to be reported in 2012 and into 2013. An increase during winter 2012 and spring 2013 was again observed, but the number of confirmed herds was lower than in the previous year. SBV spread rapidly throughout Europe from the initial area of detection. SBV was detected above the latitude of 60° North, which exceeds the northern expansion observed during the bluetongue virus serotype 8 epidemic in 2006–2009. The impact of SBV was calculated as ratio of the number of herds with at least one malformed SBV positive foetus and the total number of herds in this region. The 75th percentile of the malformations ratio in the various affected countries for the whole reporting period was below 1% and 3% for cattle and sheep herds, respectively. International data collection on emerging diseases represents a challenge as the nature of available data, data quality and the proportion of reported cases may vary widely between affected countries. Surveillance activities on emerging animal diseases are often structured only for case detection making the estimation of infection/diseases prevalence and the investigation of risk factors difficult. The impact of the disease must be determined to allow risk managers to take appropriate decisions. Simple within-herd impact indicators suitable for emerging disease outbreaks should be defined that could be measured as part of routine animal health surveillance programmes and allow for rapid and reliable impact assessment of emerging animal health diseases. 相似文献
999.
生物措施水土保持机理综述 总被引:1,自引:0,他引:1
植被能有效控制水土流失,被公认为水土保持最有效最根本的方法,因此水土流失区植被的恢复和建造成为水土保持工作的中心之一。通过对大量研究进行总结,进一步从机理上分析了植被对水土保持的作用,主要包括植被冠层对降雨的截留及对降雨侵蚀动能的影响,地表枯枝落叶层的水土保持作用和地下根系提高土壤抗冲性等。 相似文献
1000.