Neuropathology of brain myxosporean disease of fish

鱼类脑粘孢子病的神经病理学

• 批准号: 17580157
• 负责人: YOKOYAMA Hiroshi
• 金额: $ 1.86万
• 依托单位: THE UNIVERSITY OF TOKYO
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17580157/
• 关键词: myxosporean; spinal curvature; Myxobolus; neuropathology; aquaculture; brain; 脊椎彎曲

1.Pathological analysis of skeletal deformity of cultured fish : Diseased Japanese mackerel (Scomber japonicus) exhibited dorso-ventral curvature externally. Histopathological examination revealed that the spinal curvature was caused by a brain myxosporean, Myxobolus acanthogobii. Myxosporean cysts were found in the olfactory lobe, optic lobe, the cavity of optic tectum and the fourth ventricle. However, the anatomical location of cysts responsible for the skeletal abnormalities could not be determined.2.Pathological analysis of naturally infected but subclinical wild fishes : Brown-lined puffer (Canthigaster rivulata) and yellowfin goby (Acanthogobius flavimanus) were found to be naturally infected with M.acanthogobii, but did not show any skeletal abnormalities. Histopathological observation showed that numerous cysts were found in the optic lobe, medulla oblongata and cerebellum.3.Development of PCR-based detection method for M.acanthogobii-A PCR method targeting SSU rDNA of M.acanthogobii was developed. Nested-PCR analysis was applied to epizootiological survey of the parasite in feral fishes (37 species). As a result, forksnout searobin (Lepidotrigla alata) and crimson seabream (Evynnis japonica) were found to be the hosts for M.acanthogobii. Further, surveys on possible alternate annelid hosts for M.acanthogobii were conducted, but actinosporeans and PCR-positive reactions were not obtained.4.Experimentally induced abnormal behavior of fish caused by implant by brain surgery : Glass beads (ca.1 mm in diameter) were implanted in the 4th ventricle of goldfish, and swimming behavior was observed. As a result, the experimental fish showed a notable body curvature and whirling behavior. This suggests that spinal curvature is caused by mechanical pressure of foreign particles localized in the 4th ventricle of fish brain.

1.养殖鱼类骨骼畸形的病理分析：患病的日本鲭鱼（Scomber japonicus）外表呈背腹弯曲。组织病理学检查显示脊柱弯曲是由脑粘菌引起的，粘菌是棘骨粘菌。鼻叶、视叶、视顶骨腔及第四脑室可见黏液孢子囊肿。然而，导致骨骼异常的囊肿的解剖位置无法确定。自然感染的亚临床野生鱼类的病理分析：褐纹河豚（Canthigaster rivulata）和黄鳍虾虎鱼（Acanthogobius flavimanus）被发现自然感染了棘鱼绦虫，但没有表现出任何骨骼异常。组织病理学观察显示，视叶、延髓和小脑内可见大量囊肿。建立了一种以棘鱼单胞菌SSU rDNA为靶点的PCR检测方法。采用巢式pcr方法对37种野生鱼类寄生虫进行流行病学调查。结果表明，叉嘴海鲷（Lepidotrigla alata）和深红色海鲷（Evynnis japonica）是棘鱼的寄主。此外，对可能的替代环节动物宿主进行了调查，但没有获得放线菌和pcr阳性反应。脑外科植入引起的实验诱导鱼类异常行为：将直径约为1 mm的玻璃微珠植入金鱼第四脑室，观察其游动行为。结果，实验鱼表现出明显的身体弯曲和旋转行为。这表明脊柱弯曲是由位于鱼脑第四脑室的外来颗粒的机械压力引起的。

项目成果

A PCR method to detect Myxobolus acanthogobii (Myxozoa : Myxosporea), the causative agent of skeletal deformities of marine fishes

一种 PCR 方法，用于检测引起海洋鱼类骨骼畸形的 Myxobolus acanthogobii（Myxozoa：Myxosporea）

• 发表时间: 2005
• 期刊: Fish Pathology 40(4)
• 作者: Kita-Tsukamoto K;et al.;栗田 学;栗田 学;Manabu Kurita;Miyajima S. et al.
• 通讯作者: Miyajima S. et al.

Spinal curvature of cultured Japanese mackerel Scomber japonicus associated with a brain myxosporean, Myxobolus acanthogobii

与脑粘孢子类 Myxobolus acanthogobii 相关的养殖日本鲭鱼的脊柱弯曲

• 发表时间: 2005
• 期刊: Diseases of Aquatic Organisms 66(1)
• 作者: Yokoyama H;Freeman MA;Itoh N;Fukuda Y
• 通讯作者: Fukuda Y