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21.
Experimental Mycotoxic Nephropathy in Pigs Provoked by a Diet Containing Ochratoxin A and Penicillic Acid 总被引:8,自引:0,他引:8
Stoev SD Vitanov S Anguelov G Petkova-Bocharova T Creppy EE 《Veterinary research communications》2001,25(3):205-223
Mycotoxic nephropathy was induced in 18 young pigs by diets contaminated with strains of Aspergillus ochraceus containing ochratoxin A (OTA) and penicillic acid (PA) at levels corresponding to those naturally encountered in animal feeds in Bulgaria. Haematological and biochemical parameters, as well as the morphological and ultrastructural changes in various internal organs, and especially in the kidneys, were examined at different stages of development of the disease. A mottled surface of the kidneys was only seen in pigs exposed to a mouldy diet containing 180 ppb OTA for 3 months, but microscopic lesions, as well as changes in various haematological and biochemical parameters, were observed in all groups exposed to the same mouldy diet containing only 90 or 180 ppb OTA. Histological examination showed two types of change: degenerative changes affecting the epithelial cells of the proximal tubules, which predominated at the initial stage, and proliferative changes in the interstitium, which predominated at the later stage of the disease. Telangiectasis and lymph stasis were also seen, as well as degenerative changes in the capillary endothelium. The characteristic renal lesions were similar to those observed in spontaneous cases of mycotoxic porcine nephropathy in Bulgaria, but they were a little different from the classic Danish porcine nephropathy. The enhanced toxicity of OTA in our study may be due to a synergistic effect between OTA and PA or to some other unknown metabolites produced by the same ochratoxinogenic strains of A. ochraceus. 相似文献
22.
Pine Wilt Disease Caused by the Pine Wood Nematode: The Induced Resistance of Pine Trees by the Avirulent Isolates of Nematode 总被引:6,自引:0,他引:6
Hajime Kosaka Takuya Aikawa Nobuo Ogura Katsuhiro Tabata Tomoya Kiyohara 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(7):667-675
Since the beginning of the 20th century, pine trees in Japan have been seriously damaged by the pine wilt disease. This disease is caused by the pine wood nematode, Bursaphelenchus xylophilus, which is transmitted by the Japanese pine sawyer, Monochamus alternatus. The control of disease depends to a large extent on chemicals, but the public is now demanding environmentally friendly control methods. The virulence of B. xylophilus varies very widely. Pre-inoculation of young pine trees in a nursery with avirulent B. xylophilus has induced systemic resistance of trees against a subsequent inoculation with virulent B. xylophilus. This induced resistance was considered a hopeful means for developing a biological control for the disease. The induced resistance by the avirulent nematodes was also expressed in mature pine trees in a forest where the disease was naturally epidemic. However, the effects of induced resistance were not satisfactory for practical biological control. Since the inoculation with higher concentrations of the avirulent B. xylophilus induced the resistance more effectively, the pre-inoculation method will need to be improved to develop the biological control. The induced resistance of pine trees by avirulent B. xylophilus should be one of the candidate biological control methods against pine wilt disease. This induced resistance also provides an experimental system to clarify physiological interactions between the nematodes and pine trees. 相似文献
23.
2002年我国小麦条锈病发生回顾 总被引:58,自引:2,他引:56
2002年小麦条锈病是继 1950年、1964年和 1990年后在全国范围内又一次大流行 ,其发生面积近 670万hm2,损失小麦约 10亿kg。发生区域涉及甘、陕、川、渝、云、贵、宁、鄂、豫、鲁、冀等 11个省 (市 )区。 2001年冬季和2002年春季气候适宜 ,以条中 32号小种为代表的毒性菌系的发展 ,使我国绝大部分主栽小麦品种不抗病 ,出现了条锈病发生早、发展快和发生重等特点 ,促成了 2002年我国小麦条锈病的流行。尽管 2002年条锈病发生范围广 ,但损失少于 1990年。提出了以品种抗病性利用及小麦抗病性变异和病菌群体动态监测、药剂和农业防治相结合 ,病害发生流行预测预报和条锈菌菌源基地治理为主的持续治理策略。 相似文献
24.
Bricarello PA Gennari SM Oliveira-Sequeira TC Vaz CM Gonçalves de Gonçalves I Echevarria FA 《Veterinary research communications》2002,26(6):447-457
Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L3
H. contortus per kg live weight and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs. 相似文献
25.
Sixteen lambs exhibiting hepatogenous photosensitization (alveld) after grazing pasture containing Narthecium ossifragum and seven nonphotosensitized lambs grazing the same pastures were studied. All the alveld-affected lambs revealed liver damage dominated by single cell necrosis, portal fibroplasia and bile duct proliferation. Crystalloid clefts were demonstrated in the bile ducts of two and in the hepatocytes and Kupffer cells of nine photosensitized lambs. Plasma bilirubin concentration was severely increased in ten of the cases of alveld whereas the activity of aspartate aminotransferase was moderately to severely increased in seven cases. The activity of glutamate dehydrogenase was moderately elevated in one of the photosensitized lambs. The main histopathological findings in the kidneys from the alveld-affected lambs were dilated tubules, often with eosinophilic material in the tubular lumina. Regenerative changes were seen in a large proportion of the renal sections. Elevated plasma concentrations of urea and creatinine, and the renal histopathological changes, suggested that the photosensitized lambs had been through a phase of renal injury. Analysis of the free and conjugated sapogenin content in liver tissue and bile was performed by gas chromatography–mass spectrometry. There were significantly higher concentrations of conjugated episapogenins in both the liver and bile in the alveld-affected lambs than in the nonphotosensitized lambs. 相似文献
26.
Sikdar A Chakraborty GC Bhattacharya D Bakshi S Basak DK Chatterjee A Halder SK 《Tropical animal health and production》2000,32(3):165-171
Gangrenous syndrome/Degnala disease was recorded in a large number of buffaloes and cattle in Murshidabad district of West Bengal, India. Fusarium spp. had been isolated from the mouldy paddy straw which were fed to the animals. There was a reduction in the incidence of the disease following withdrawal of the mouldy paddy straw. Histopathological examination showed necrosis and loss of architectural details in the skin. 相似文献
27.
Amy E. DeClue DVM MS DACVIM Leah A. Cohn DVM PhD DACVIM 《Journal of Veterinary Emergency and Critical Care》2007,17(4):340-347
Objective: To review the clinical and pathophysiologic aspects of acute respiratory distress syndrome (ARDS) in dogs and cats. Data sources: Data from human and veterinary literature were reviewed through Medline and CAB as well as manual search of references listed in articles pertaining to acute lung injury (ALI)/ARDS. Human data synthesis: Since the term ARDS was first coined in 1967, there has been a abundance of literature pertaining to this devastating syndrome in human medicine. More complete understanding of the complex interactions between inflammatory cells, soluble mediators (e.g., tumor necrosis factor, interleukin (IL)‐6, IL‐8, platelet activating factor) and the clinical patient has provided for timely recognition and mechanistically based protective strategies decreasing morbidity and mortality in human patients with ARDS. Veterinary data synthesis: Although little is known, ARDS is becoming a more commonly recognized sequela in small animals. Initial case reports and retrospective studies have provided basic clinical characterization of ARDS in dogs and cats. Additionally, information from experimental models has expanded our understanding of the inflammatory mechanisms involved. It appears that the inflammatory processes and pathologic changes associated with ARDS are similar in dogs, cats, and humans. Conclusions: Unfortunately, current mortality rates for ARDS in small animals are close to 100%. As our capability to treat patients with advanced life‐threatening disease increases, it is vital that we develop a familiarity with the pathogenesis of ARDS. Understanding the complex inflammatory interactions is essential for determining effective preventative and management strategies as well as designing novel therapies for veterinary patients. 相似文献
28.
29.
蛋鸡中发现J亚群白血病与网状内皮增生症自然混合感染 总被引:12,自引:3,他引:12
发病蛋鸡经组织学、免疫组化检测确诊为J亚群白血病与网状内皮增生症混合感染。与人工接种病例不同的是,在肿瘤组织内还发现一种特殊的细胞——淋巴-巨噬细胞;在骨髓和肿瘤组织中检测到部分髓细胞胞浆内有ALV—J抗原表达。从发病情况、各器官病变程度及免疫组化结果来看,2种病原存在明显的相互协同作用,脾可能是网状内皮增生症的原发器官。但其发病的时间可能不如J亚群白血病早。此次在蛋种鸡发现此混合感染提示,病毒在环境选择压及免疫选择压的作用下,其生物特性、致病作用以及宿主范围均可发生改变。应警惕J亚群白血病和网状内皮增生症混合感染在蛋鸡中的大面积暴发。 相似文献
30.