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51.
Ruehl-Fehlert C Bomke C Dorgerloh M Palazzi X Rosenbruch M 《Journal of fish diseases》2005,28(11):629-637
Pleistophora infestation was observed in adult fathead minnows, Pimephales promelas, held under laboratory conditions. Fish were clinically healthy, and presented no gross findings at necropsy. Histopathology revealed parasitic stages only in the ovaries. Spores within sporophorous vesicles were mainly encountered in late vitellogenic oocytes and were ultrastructurally identified as a microsporidian parasite. Heavily parasitized oocytes underwent degeneration followed by the release of spores into the ovarian interstitium. Degenerating oocytes and interstitial spores caused ovarian inflammation. Male fish showed no parasites in the testes. Parasitic infestation was compared with body length, body weight, gonadal weight, gonadosomatic index and plasma vitellogenin levels, and revealed no statistically significant differences between non-parasitized and parasitized females. The isolated holding conditions of the fish and the presence of parasitic stages in the ovaries suggested that an infestation with Pleistophora ovariaeSummerfelt, 1964 was more probable than that with Pleistophora mirandellae (Vaney & Conte, 1901). 相似文献
52.
Multiple greyish‐white visceral nodules containing abundant rapidly growing and acid‐fast bacteria, subsequently identified as Mycobacterium salmoniphilum, were detected in moribund and newly dead market‐sized fish during a period of increased mortality in an Atlantic salmon, Salmo salar, farm in western Norway. Isolates cultured from diseased fish were phenotypically consistent with Mycobacterium sp. previously isolated from Atlantic salmon [MT 1890 (= NCIMB13533), MT1892, MT1900 and MT1901] in the Shetland Isles, Scotland. Partial sequences of 16S rDNA, ribosomal RNA internal transcribed spacer (ITS1), 65‐kDa heat‐shock protein (Hsp65) and β subunit of RNA polymerase (rpoB) revealed 97‐99% similarity with M. salmoniphilum type strain ATCC 13758T. The source of infection was not confirmed. Koch’s postulates were fulfilled following experimental challenge of Atlantic salmon with field isolate NVI6598 ( FJ616988 ). Mortality was recorded in experimentally infected fish; however, the infection remained subclinical in the majority of affected fish over the 131‐day challenge period. 相似文献
53.
家兔亚硒酸中毒的病理形态学研究 总被引:1,自引:0,他引:1
给家兔分别肌肉注射不同剂量的亚硒酸钠,历时入周,复制出亚急性硒中毒的动物模型。病理形态学变化为:家兔的生长受到明显抑制,肝,肾,心,脾等组织器官损害严重如肝实质细胞变性,坏死;肾实质退行病变;心肌纤维变性,充血,肺淤血,水肿:脾萎缩,淋巴细胞坏死,肝,肾,心细胞内线粒高度肿胀,嵴减少,断裂或消失成空泡。 相似文献
54.
选用SPF种蛋孵化的京白鸡60只,随机分为三组,即马立克氏病单价苗组(2000PFU HVT)、双价苗组(2000 PFU HVT 1200 PFU SB—1)以及攻毒对照组.应用组织学和透射电镜等手段对两种疫苗的免疫保护效应进行了比较病理学研究.结果证明,双价苗免疫鸡,MD发病数显著减少,发病时间推迟,病变程度明显减轻,法氏囊有大量具有分泌活性的浆细胞;单价苗免疫鸡发病数较对照组略有减少,但对延缓或减轻MD肿瘤的发生无明显作用,在法氏囊网状细胞胞浆中、核碎片附近和细胞间隙中存在大量无囊膜的马立克氏病病毒粒子,残存的细胞发生变性、坏死.由此认为,双价苗对实验性鸡马立克氏病的免疫效果明显优于HVT单价苗. 相似文献
55.
PJ CANFIELD L. VOGELNEST ML CUNNINGHAM GS VISVESVARA 《Australian veterinary journal》1997,75(2):97-100
Objective
To describe a case of meningoencephalitis caused by Balamuthia mandrillaris in an orang utan.
Design
A pathological case report.
Animal
A 20 years old male orang utan (Pongo pygmaeus).
Procedure
The disease process was investigated by clinical pathology, necropsy, histopathology and immunofluorescence labelling.
Results
The orang utan developed sudden onset of depression, lethargy, inappetence and apparent head pain. The condition was considered to be related to a 2 year history of upper and lower respiratory disease, and the animal was placed on antibiotics after extensive testing. By the seventh day the animal had become ataxic and disoriented and a brain abscess was suspected. He died on the ninth day of illness. At necropsy, and subsequent sectioning, the brain showed multiple circular, soft, white to grey brown areas of varying size, the largest being in the left temporal (3.5 cm diameter) and right occipital (2.5 cm diameter) regions of the cerebrum. Histological examination of these regions revealed many amoebic trophozoites and occasional cysts associated with areas of haemorrhage and inflammatory necrosis. The trophozoites were packed in perivascular spaces and their nuclei often contained two or more prominent nucleoli. Immunofluorescent labelling of histological sections suggested that the agent was B mandrillaris.
Clinical implications
This report provides further evidence that B mandrillaris , a free living amoeba, can act as a pathogen in animals as well as people, and cause fatal meningoencephalitis. Along with Naegleria and Acanthamoeba spp, B mandrillaris should be considered amongst the causes of acute onset meningoencephalitis in animals. 相似文献
To describe a case of meningoencephalitis caused by Balamuthia mandrillaris in an orang utan.
Design
A pathological case report.
Animal
A 20 years old male orang utan (Pongo pygmaeus).
Procedure
The disease process was investigated by clinical pathology, necropsy, histopathology and immunofluorescence labelling.
Results
The orang utan developed sudden onset of depression, lethargy, inappetence and apparent head pain. The condition was considered to be related to a 2 year history of upper and lower respiratory disease, and the animal was placed on antibiotics after extensive testing. By the seventh day the animal had become ataxic and disoriented and a brain abscess was suspected. He died on the ninth day of illness. At necropsy, and subsequent sectioning, the brain showed multiple circular, soft, white to grey brown areas of varying size, the largest being in the left temporal (3.5 cm diameter) and right occipital (2.5 cm diameter) regions of the cerebrum. Histological examination of these regions revealed many amoebic trophozoites and occasional cysts associated with areas of haemorrhage and inflammatory necrosis. The trophozoites were packed in perivascular spaces and their nuclei often contained two or more prominent nucleoli. Immunofluorescent labelling of histological sections suggested that the agent was B mandrillaris.
Clinical implications
This report provides further evidence that B mandrillaris , a free living amoeba, can act as a pathogen in animals as well as people, and cause fatal meningoencephalitis. Along with Naegleria and Acanthamoeba spp, B mandrillaris should be considered amongst the causes of acute onset meningoencephalitis in animals. 相似文献
56.
A nasal, so called ethmoidal, tumor from a fallow deer is described. It appears to be the first reported case of that species. The etiology is discussed. 相似文献
57.
文章指出了传统多媒体教学的误区——课件质量不高、教师的主导作用被减弱、学生的主体作用被忽略和学生自主学习的愿望未能很好地实现.基于Web的农业植物病理学多媒体教学课件,从课件内容的设计、课件的课堂演示及教学过程中师生的互动等三个方面有效地提高教学效果.并就未来农业植物病理学的多媒体教学改进进行了探讨。 相似文献
58.
鲤鱼细菌性败血症的病理学研究 总被引:16,自引:0,他引:16
汪开毓 《四川农业大学学报》2004,22(3):257-262
报道了由嗜水气单胞菌嗜水亚种 (Aeromonashydrophilasubsp .hydrophila)感染鲤鱼引起细菌性败血症的病理学变化 ,通过对自然感染和人工感染病例的病理学观察 ,病理变化主要表现为鱼体多处出血 ,特别是体表的出血最为明显 ,上下颌、眼睛、鳃盖、鳍基充血发红 ,皮肤有瘀斑瘀点 ,并发生糜烂、溃疡 ;腹水 ,肛门红肿外突 ;心、肝、肾、肠等内脏器官充血、出血、肿大、变性、坏死、发炎以及红细胞发生溶血等 ,表现出细菌性败血症的病理特征 ,并在病理变化观察的基础上探讨了该病发生的机理。 相似文献
59.
兔病毒性出血症是一种烈性传染病,主要发生于膘情较好的青、壮年兔,常在冬、春季节流行,临床症状和病理变化以急性败血症为特征。典型病变为肺有数量不等、大小不一的出血病灶,气管粘膜严重充血,呈紫红色,该病毒抗原能凝集人O型红细胞,这种血凝性可被病兔康复血清抑制。取病兔肝、脾,肾制成匀浆,用甲醛灭活制成的疫苗,安全性好,产生免疫力性,保护率达95%以上。 相似文献
60.
给家兔灌服低剂量(6 mg/kg)、中剂量(12 mg/kg)和高剂量(24 mg/kg)的萱草根素,研究其对家兔的毒性作用。结果显示,家兔均发生以中枢神经系统紊乱为特征的中毒症状,且存在明显的量-效关系;中毒家兔大脑、小脑和脊髓的白质呈丝瓜络样,结构异常疏松,肾小管上皮细胞肿胀、破裂,视网膜节细胞萎缩,肝细胞肿胀,颗粒变性,脾脏、肺脏严重充血。表明萱草根素能引起家兔以中枢神经系统病变为主的全身性病理变化。 相似文献