Susceptibility and immune responses of hybrid snakehead (Channa maculata♀ × Channa argus ♂) following infection with snakehead fish vesiculovirus

• Published in: Aquaculture Vol. 533; p. 736113
• Main Authors: Cao, Pan, Sun, Wei, Zhang, Yanbing, Zhou, Zicheng, Zhang, Xiaojun, Liu, Xiaodan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.02.2021
• Subjects: Histopathological analysis; Hybrid snakehead; Immune responses; Snakehead fish vesiculovirus; Susceptibility; Hybrid snakehead; Immune responses; Susceptibility; Snakehead fish vesiculovirus; Histopathological analysis
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2020.736113

Snakehead fish vesiculovirus (SHVV) was initially isolated from diseased hybrid snakehead, and could cause great economic losses in snakehead culture due to its high morbidity and mortality. In this study, the susceptibility, histopathological analysis, and host immune response of hybrid snakehead infected with SHVV were investigated. SHVV was highly pathogenic to hybrid snakehead, and the infected fish exhibited typical signs of acute haemorrhages, and enlarged visceral organs. Histopathological analysis showed that the major tissues of diseased fish exhibited obvious inflammatory responses to SHVV infection. Additionally, humoral immune factors such as superoxide dismutase (SOD), catalase (CAT), and acid phosphatase (ACP) were assayed as serum indicators to evaluate the immune responses induced in infected hybrid snakehead. Quantitative real-time PCR (qRT-PCR) was also performed to evaluate the expression patterns of immune-related genes (HSP70, IL-8, MHCIα, MHCIIα, SOD1, ZAP70, PKCθ, LCK, and HLA-A) in tissues of liver, spleen, head kidney and intestine. The results showed significantly enhanced immune activities in hybrid snakehead after SHVV infection. Altogether, these data provided insights into the pathogenic mechanism of SHVV and host immune response, facilitating the future prevention and treatment of hybrid snakehead infected with SHVV. •Snakehead fish vesiculovirus infection caused typical clinical signs and high pathogenicity to hybrid snakehead.•Obvious histopathological changes were observed in hybrid snakehead infected with SHVV.•The SOD, CAT, and ACP enzyme activity can be used as indicators of SHVV infection.•SHVV infection triggers a wide defensive response of various immune-related genes in hybrid snakehead.