Isolation and characterization of an iridovirus from sick giant salamander (Andrias davidianus) / 病毒学报

A virus was isolated from cultured sick giant salmander (Andrias davidianus ) in a farm, Shanxi Province, China. Skin ulceration and necrosis of the distal limbs are main clinical symptoms. Virus propagated and caused CPE at 10 degrees C to 30 degrees C in BF-2, CO, CHSE, FHM cells. The optimum condition of replication was in BF-2 cells at 25 degrees C. The virus was proved to be senstive to chloroform, heat, pH3 and pH10 treatment. Viral replication was inhibited by 5-Fluoro-2-deoxyuridine (FUDR). These results indicated that the virus possessed an envelope and DNA as the genome. Electron-microscopic observation of thin-section showed numerous hexagonal viral particles measuring 130 nm to 150 nm in diameter orderly arranged in a lattice form in cytoplasm of BF-2 cells. The particles showed typical iridovirus morphology. A 413 bp fragment was amplified from the viral main capsid protein gene by PCR. The fragments was sequenced and analysed. The results showed the isolate shared more than 96% nucleotide identity with some Ranaviruses. We suggested that this virus was named as Andrias davidianus iridovirus (ADIV) tentatively.

Comparison of characteristics of SVCV strains isolated in China and in Europe / 病毒学报

In the nationwide epidemiological investigation, SVCV-741 was for the first time isolated in Beijing region, China in 2003, and designated as SVCV Asian strain. In this paper, we compared SVCV-741 (Asian strains isolated in China) with SVCV-10/3 (Europe reference strain) on their physico-chemical, biological and morphological characteristics. The results indicated that there were no distinct differences between two SVCV strains on phycico-chemical and morphological characteristics. The main existing differences were: (1) The stability of SVCV-741 to temperature in cell culture was higher than that of SVCV-10/3, which might have some evolutionary and biological implication of SVCV; (2) No SVC outbreak ever occurred caused by SVCV-741;Furthermore we found that both SVCV-741 and SVCV-10/3 grew faster and produced higher virus titer in CO cells than other cell lines. It indicated that CO cell lines might be useful tool for SVCV research.