Distribuzione di Lymphocystivirus in organi target e non target di orate (Sparus aurata) naturalmente infette

Abstract

Lymphocystis is a cutaneous viral disease, caused by a virus (LCDV) of genus Lymphocystivirus, family Iridoviridae. The disease is frequently benign and in the Mediterranean area it affects mainly Gilthead seabream (Sparus aurata). This disease, in seabream farms, causes significant economic losses related to poor growth rate, non-marketability of fish with lesions and mortality due to secondary infections. LCDV infection causes single or clustered tumour-like cutaneous nodules. Histology, generally, does not evidence lesions in internal organs, however, recent studies have revealed the systemic spread of the virus. The in vitro isolation of LCDV is difficult, reducing the possibilities of pathogenetical investigations on lymphocystis. Recently, our research team has developed a real time PCR (qPCR) assay able to detect and quantify the LCDV DNA both in diseased and recovered fish. In this study, the qPCR assay has been applied to detect the LCDV DNA in target (pectoral and caudal fins) and not target (spleen, brain and eyes) organs of Gilthead seabream at different clinical stage (diseased/in regression) and asymptomatic. This study has revealed the viral DNA presence in both target and not target organs with statistically higher values in pectoral and caudal fins than in internal organs. Diseased, in regression and asyntomatic fish have shown similar viral DNA distribution