眼斑拟石首鱼虹彩病毒病的诊断

对广东省珠海市每年6—10月池塘养殖的眼斑拟石首鱼(Sciaenop socellatus)暴发不明原因疾病进行了研究。通过对该病的流行病学调查，结合症状观察、病原分离鉴定、病理学变化，结果显示:该病具有明显的传染性，解剖病鱼可见鳃丝贫血、脾脏和肾脏肿大、出血，通过镜检未检测到大量的寄生虫；从发病鱼的肝、脾、肾脏和肠中未分离到致病菌；在病鱼肝、脾和肾组织病理切片中观察到有大量肿大细胞；通过使用OIE 推荐的虹彩病毒特异性引物进行PCR扩增出570 bp左右的目的片段，MCP基因序列比对显示扩增获得的基因序列与真鲷虹彩病毒(RSIV)的基因序列同源性高达99.2%。综合以上结果表明导致眼斑拟石首鱼发病死亡的原因是感染了细胞肿大属虹彩病毒而引起的虹彩病毒病。

DIAGNOSIS OF IRIDOVIRUS DISEASE IN SCIAENOP SOCELLATUS

The epidemiological investigation, symptom observation, pathogenic detection, and the pathology detection were used to examine the cause of the disease of Sciaenop socellatus of cultured pond in Zhuhai, Guangdong Province from June to October. These results showed that the disease had obvious infectious. The anatomy examination revealed the anemia of the gill filament, swollen spleen and kidney with hemorrhagic spots, and no observed large number of parasites by microscopy. Meanwhile, no pathogenic bacteria were isolated from the liver, spleen, kidney and intestine of the diseased fish. A large number of swelling cells were observed in pathological sections of liver, spleen and kidney of diseased fish. The 570 bp fragment was amplified by PCR using the specific primers of OIE. MCP sequence alignment showed that the amplification of the gene sequence had 99.2% of homology with gene sequence of RSIV. The comprehensive results showed that the cause of the disease of the Sciaenop socellatus is infected by the iridovirus of Megalocytivirus genus.