Ranavirus (family Iridoviridae) detection by polymerase chain reaction (PCR) in Chinese giant salamander (Andrias davidianus, Blanchard, 1871), China

Abstract

A disease in farmed Chinese giant salamander (Andrias davidianus) was a common event, being an economically important threat for Chinese farms. Based on the clinical signs, epizootiology and pathogens belonging to the genus, Ranavirus was suspected as the possible etiology. Although in a cultured Chinese giant salamander (Andrias davidianus) farm in Hanzhong County, Shanxi Province, China, a ranavirus infection case had been reported, the presence in other farms was never mentioned so far. The objective of this study was to detect the presence of ranaviral agents in affected Chinese giant salamanders using polymerase chain reaction (PCR) assay. Major capsid protein (MCP) gene was selected as the targets to amplify the high conserved fragment. Positive PCR results were obtained when sick Chinese giant salamanders from Sichuan and Gansu Province were analyzed. Purified and sequenced PCR products showed high degree of identity with several members of Iridoviridae, mostly with those belonging to the genus Ranavirus in GenBank BLAST searches. Obtained sequences were registered in the GenBank with accession numbers HQ684750, JN590256 and JN651174. This report indicated that Ranavirus should be considered a common disease etiology throughout these geographical regions.

Key words: Polymerase chain reaction (PCR), iridovirus, Ranavirus, Andrias davidianus, Chinese giant salamander.