天津地区1例患病鳜的病原学初步鉴定与分析

Preliminary Identification and Analysis of the Pathogen of Siniperca chuatsi Disease in Tianjin

摘要: 本研究采用流行病学调查、分子生物学等方法对天津地区某养殖场采集的患病鳜(Siniperca chuatsi)开展了病原学研究工作。水浸片和细菌分离鉴定结果显示：患病鳜未发现寄生虫和有害细菌的感染；病原学检测结果显示：鳜鱼弹状病毒、神经坏死病毒、传染性脾肾坏死病毒检测结果均为阴性，鳜鱼蛙病毒检测结果为阳性，目标产物大小为1392 bp (GenBank No.: PQ212952.1)；经NCBI BLAST序列比对和系统发育树分析结果显示：分离自患病鳜的蛙病毒主要衣壳蛋白(MCP)基因序列与分离自大口黑鲈、孔雀鱼及黑尾海猪鱼的MCP基因序列分为一支，亲缘关系最近，相似性达到99%~100%，初步认为该患病鳜致病原为虹彩病毒科蛙病毒属类的病毒，值得引起广大养殖者及研究者的高度关注。

Abstract: In this study, epidemiological investigation, molecular biology and other methods were used to conduct pathogenic research on diseased mandarin fish (Siniperca chuatsi) collected from a breeding farm in Tianjin area. The results of water immersion and bacterial isolation and identification showed that no parasitic or harmful bacterial infections were found in the diseased mandarin fish; The pathogen detection results showed that the detection of Siniperca chuatsi rhabdovirus (SCRV), viral nervous necrosis (VNN), and infectious spleen and kidney necrosis virus (ISKNV) was all negative, while the detection of mandarinfish ranavirus (MRV) was positive. The target product size was 1392 bp (GenBank No.: PQ212952.1); The results of NCBI BLAST sequence alignment and phylogenetic tree analysis showed that the major capsid protein (MCP) gene sequence of MRV isolated from diseased mandarin fish was closely related to the MCP gene sequence isolated from largemouth bass, guppy, and Halichoeres melanurus, with a similarity of 99%~100%. It is preliminarily believed that the pathogen of this diseased mandarin fish is a virus belonging to the family Iridoviridae and the genus of ranavirus, which deserves high attention from breeders and researchers.