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81.
An increasing number of laboratory tests are available for diagnosis of gastrointestinal tract diseases in dogs and cats. Use of these tests can lead to more accurate and rapid diagnoses. This review discusses laboratory tests, both new and old, and the role they currently play in the evaluation of animals presented with gastrointestinal problems. A minimum database helps assess the severity of the disorder, detect extra-gastrointestinal causes of problems and assists in formulating diagnostic and therapeutic plans.

Faecal examination remains one of the most important diagnostic procedures in the investigation of gastrointestinal problems. Zinc sulphate faecal flotation is an excellent routine screening technique for helminth and protozoal infections, including giardiasis. Rectal cytology can assist in the diagnosis of large bowel disorders. Interpretation of faecal immunodiagnostic tests is hampered by insufficient knowledge of test sensitivities and specificities. Routine faecal cultures are not warranted and faecal occult blood tests are rarely indicated.

Serum tests for gastric inflammation are now under development. The serum trypsin-like immunoreactivity test remains the gold standard technique for the diagnosis of exocrine pancreatic insufficiency. Breath hydrogen tests can be helpful in assessing the functional relevance of mild abnormalities in small-bowel biopsy specimens. Subnormal concentrations of serum cobalamin appear to be more specific indicators of gastrointestinal disease in cats than in dogs. Tests for small intestinal bacterial overgrowth remain controversial and assessment of gastrointestinal permeability has yet to prove its value in the diagnostic assessment of companion animals with gastrointestinal problems. Faecal alpha1-protease inhibitor (α1-PI) shows promise for the diagnosis of protein-losing enteropathy.  相似文献   
82.
为探讨酸化和渗透压不同处理顺序对肠炎沙门菌失活的影响,运用统计学模型模拟了最优处理条件下,肠炎沙门菌在不同初始接菌量下的失活过程。实验结果表明:在25℃和10 h内,先15%Na Cl再p H值4.5处理使肠炎沙门菌失活的效果大于相反顺序的处理、同时处理或者单独处理的效果。模拟结果表明:在最优处理条件下的各个阶段中,随着初始接菌量的增加,肠炎沙门菌分别达到0.986 4和0.993 9失活率时对应的失活时间的变异性逐渐降低。对于大量群体细菌,用确定性失活动力学一级模型拟合的D值是单一的定值;而对少量群体细菌,由于个体细胞本身的变异性,D值表现出较高的变异性,并且可用概率分布的形式表示。酸化和渗透压不同处理顺序的研究能为食品工业生产控制致病菌提供借鉴,且应用的统计学建模方法有助于从个体细胞的角度理解群体失活过程,提高风险评估的准确性。  相似文献   
83.
The alimentary tract is a possible site where pathogens and toxins can enter. The alimentary tract is protected, amongst others, by mucus. In this study, tissue samples and crude mucus preparations from different parts of the intestinal tract of Cyprinus carpio (from intestinal bulb onto the hindgut) were examined using histological, histochemical and biochemical techniques. Furthermore, the response of the intestinal mucosal layer and intestinal mucus of C. carpio to acute soybean meal (SBM)‐induced enteritis was investigated. In the present study, an indication for a different protein core of mucus high molecular weight glycoproteins (HMGs) for first and second segment could not be found. However, differences in mucus glycosylation could be found. Along the gut axis, the size of the major protein peaks were not similar, which can be caused by a different glycosylation. Also, differences in staining for the antimicrobial peptide beta‐defensin 2 were found. Furthermore, changes in HMGs upon SBM diet were found similar to those found in inflammatory bowel disease (IBD) in humans. Initial changes include: changes in mucin composition, the presence of BD3 and of bacteria in internal organs. After the initial changes, all values measured returned back to the initial pre‐SBM diet values.  相似文献   
84.
检测石蜡切片中鸭病毒性肠炎病毒间接原位PCR方法的建立   总被引:3,自引:0,他引:3  
 【目的】建立能对石蜡切片中鸭病毒性肠炎病毒(DEV)核酸进行定位的原位PCR方法,为鸭病毒性肠炎(DVE)存档蜡块的回顾性诊断、致病机理研究等提供有效的实验手段。【方法】据DEV的UL30-UL31基因序列设计PCR引物和寡核苷酸探针,以DEV感染死亡鸭肝脏组织石蜡标本制作切片,经蛋白酶K消化、原位PCR扩增和生物素标记的寡核苷酸探针原位杂交,建立了检测石蜡标本中DEV的间接原位PCR方法并应用于人工感染DEV不同时间的鸭肝脏、DVE发病鸭的存档蜡块和临床病料检测。【结果】间接原位PCR对DVE死亡鸭肝脏的石蜡标本检测结果为阳性,而鸭病毒性肝炎、鸭疫里默氏杆菌病、鸭多杀性巴氏杆菌病、鸭沙门氏菌病和鸭大肠杆菌病死亡鸭肝脏的石蜡标本检测结果为阴性;间接原位PCR对人工感染DEV后2、4、6、12、24、48和72 h不同时间的鸭肝脏检测结果均为阳性,阳性细胞有肝细胞、窦皮细胞和枯否氏细胞,阳性信号多出现于坏死细胞的碎片中或细胞坏死后形成的空泡内及空泡边缘;对存档蜡块、临床病料的检测与病毒分离鉴定吻合率为100%。【结论】本研究建立的间接原位PCR方法具有直观、敏感、特异性强的优点,在显示核酸阳性信号的同时,还能判别含有靶序列的细胞类型以及组织细胞的形态结构特征与病理变化。可用于DVE的诊断、分子流行病学调查、存档蜡块的回顾性诊断和致病机理的研究。  相似文献   
85.
This study investigated morphological changes associated with soya bean meal‐induced enteritis (SBMIE) in distal intestine (DI) of rainbow trout (Oncorhynchus mykiss) fed a soya bean meal (SBM)‐based diet and exposed to normoxia or hypoxia created by optimal and low water flow rates, respectively. A 28‐day adaption period was followed by a 42‐day challenge period where 600 fish were subjected to dietary challenge and/or hypoxia. Twelve tanks each containing 50 juvenile trout were assigned randomly in triplicate to each treatment. Histopathological and immunohistochemical evaluation revealed pathological features that have not previously been described in association with SBMIE. Vacuolar degeneration of epithelial cells mainly at the base of mucosal folds, epithelial cysts, epithelial dysplasia, necrosis, shedding of necrotic cells, and granulomatous inflammation including infiltration of enlarged, sometimes finely vacuolated or “foamy” macrophages, multinucleated giant cells and increased proliferation of fibroblasts were observed. Acid‐fast bacteria were not detected in enlarged macrophages; however, these cells contained AB‐PAS‐ and sometimes cytokeratin‐positive material, which was interpreted to be of epithelial/goblet cell origin. Hypoxia did not affect the morphological changes in DI. These results suggest that SBM was associated with a granulomatous form of enteritis in DI of rainbow trout regardless of water oxygen level.  相似文献   
86.
1. This study investigated the prebiotic properties of arabinoxylo-oligosaccharides (AXOS) produced both in situ and in vitro for their activity against the onset of necrotic enteritis in broiler chickens.

2. A 2 × 3 factorial arrangement was applied, including necrotic enteritis challenge (challenged/unchallenged) and three dietary treatments from d 10 to 21. A wheat–soy commercial-type basal-grower diet was fed with 2% of the wheat proportion replaced by the same amount of either arabinoxylan (AX), AXOS produced from hydrolysing AX with 16 000 BXU (birch xylanase unit) xylanase in vitro or AX fed with 16 000 BXU xylanase (AX + E). Necrotic enteritis (NE) challenge was induced by orally infecting birds with a vaccine strain of Eimeria oocysts at d 9 of age followed by oral gavage of a freshly prepared Clostridium perfringens broth at d 14.

3. The challenge depressed growth performance, induced gross lesions and reduced ileal viscosity at d 10–21. Birds fed on the AXOS diet had numerically less severe gross lesions, improved feed conversion at d 0–16 and lower ileal viscosity at d 16 compared to birds fed on AX. Weight gain of the unchallenged birds ranked as follows in terms of the diets: AXOS > AX + E > AX. AX + E produced a lower ileal viscosity compared to the AX treatment but only led to marginal improvements in performance and intestinal lesion scores.

4. Caecal short-chain fatty acid (SCFA) concentration was higher in birds fed on AXOS and AX + E compared to those fed on AX and was higher in the challenged birds compared to the unchallenged birds. Gizzard pH was lower in birds fed on AX + E compared to those fed on AXOS at d 16. Challenged birds had lower ileum pH compared to the unchallenged birds at d 16 and 21.

5. Results of this study suggest that AXOS appeared to be efficacious prebiotics, as highlighted by improvements in feed conversion ratio and increased SCFA production. Future studies are warranted to elucidate the types of AXOS that are most active against NE and the mechanisms by which different levels of AXOS enhance bird performance.  相似文献   

87.
畜禽坏死性肠炎主要是由产气荚膜梭菌引起的一种急性消化道传染病,具有较高的发病率和死亡率。该病不仅损害畜禽健康,影响动物福利,而且对养殖业发展及人类健康造成了严重威胁。抗菌药的出现对该病起到了积极限制的作用,然而随着抗菌药的不合理使用,耐药菌株不断增加,坏死性肠炎的发病率呈现升高的趋势,防制坏死性肠炎面临严峻挑战。作者从坏死性肠炎的特征入手,综述了坏死性肠炎的病原学、理化特性、流行病学、临床症状等,与此同时对坏死性肠炎的防制措施及目前常用药物进行了总结,客观分析了防制坏死性肠炎的趋势与发展方向,旨在健全对该病的认识,为坏死性肠炎的防制研究提供参考。  相似文献   
88.
对采自白城市的疑似鹅病毒性肠炎的病死雏鹅病料,经过病毒分离培养、中和试验、动物回归试验和PCR检测,证明所分离的病毒确为鹅病毒性肠炎病毒。  相似文献   
89.
Intestinal lymphangiectasia (IL) is a common complication in dogs. Since nitric oxide (NO) is known to relax the lymphatic vessel, we evaluated inducible NO synthase (iNOS) expression using immunohistochemistry in 13 dogs with lymphoplasmacytic enteritis (LPE) with or without IL. The duodenal iNOS expressing cells were significantly increased in dogs with IL-negative or IL-positive LPE dogs (P=0.025, P=0.007) compared with control dogs. However, there was no significant difference in iNOS expression between IL-positive and IL-negative tissues. Based on these results, there is no clear evidence for the NO overproduction in the pathogenesis of IL in dogs with LPE. Factors other than NO could, thus, contribute to IL in dogs with LPE.  相似文献   
90.
T-cell-mediated hypersensitivity could be central in soybean meal (SBM)-induced intestinal changes in salmon. However, tools for immunohistochemical detection of T cells have been lacking in teleosts, including Atlantic salmon. Application of a specific histochemical protocol allowed demonstration of T-cell-like reactivities in formalin-fixed, paraffin-embedded tissues using an antibody reacting to a conserved region of human CD3epsilon (Dako A0452). Characteristic staining was observed in cells of the thymus as well as distal intestine, skin, gills and spleen. These cells were negative for immunoglobulin M (IgM). Intestinal intraepithelial leucocytes were CD3epsilon positive. During the SBM-induced enteropathy, the mixed inflammatory infiltrate in the lamina propria of the distal intestine included many lymphocytes with a T-cell-like reactivity. Real-time polymerase chain reaction revealed significantly increased expression of a complex polypeptide (CD3pp), CD4 and CD8beta (P < 0.05) in the distal intestine of SBM-fed fish compared to fish meal-fed reference fish. Increased reactivity for extracellular IgM in the lamina propria and a positive material between the epithelial cells at the tips of the folds was observed, possibly due to leakage of IgM through an abrogated epithelial barrier. In conclusion, a T-cell-like response appears to be involved in this example of a food-sensitive enteropathy.  相似文献   
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