Isolation, Identification, and Pathogenicity Characterization of a Largemouth Bass Ranavirus from Fujian, China

• DOI: 10.4194/trjfas25307
• Publication Date: 2024-03-18T10:13:02Z
• Authors: Jin-Xian Yang; Xi Chen; Hua Chen; Jun-Qing Ge
• Keywords: Ranavirus; Iridovirus; Isolation; Identification

This study aimed to isolate and characterize the pathogenic agent of a suspected viral disease largemouth bass (Micropeterus salmoides), which broke out in an aquatic farm Fujian, China. The diseased had ulcer skin muscles, bleeding fin, lesion liver, enlarged spleen. Histopathological analysis showed multifocal necrosis on gill, hepatopancreas spleen, kidney. In epithelioma papulosum cyprinid (EPC) cell line, stable cytopathic effects (CPE) were observed. Electron microscopy icosahedral virus particles cytoplasm with 150-160 nm diameter. PCR amplification revealed that isolated belongs ranavirus (LMBV) was designated as LMBV FJ_22109. Further phylogenetic determined FJ_22109 is variant European American strains. intraperitoneal injection resulted regress infection, demonstrating its ability induce pathogenicity bass. cumulative mortality rate 100% at culture temperature 29°C, 47% 17°C. Thus, it confirmed indeed causative disease, virulence could be influenced by temperature, will beneficial for preventing managing disease.