Abstract: An unknown disease with massive mortality of 80% was studied in spinefootSiganusfuscescenscultured in sea net cages in Dongshan County, Fujian Province from June to October. The morbid spinefoot from the cage bottom floating to the surface showed the symptoms of black body, rapid movement, and then slowstagnant, finally imbalance, even death. The postmortem examination revealed that morbid spinefoot had obviously swollen spleen and kidney with petechial haemorrhages, devoid of stomach, and bloody intestine. Epidemiological survey showed the disease had obvious infectious, and that no pathogenic bacteria and parasites were found from the organs including liver, spleen and kidney. Many enlargement and necrosis cells were histopathologically observed in the liver, spleen and kidney. The specific products with predicted size were obtained from all diseased tissues by the primers designed according to the sequence of OIE. Comparative analysis of nucleotide sequences with the GenBank databases using Blast database network service indicated that the putative gene products from infected gobies shared 98.6% identity with red sea bream iridovirus(RSIV), 97.4% identity with grouper iridovirus(GIV)and 93.2% identity with infectious spleen and kidney necrosis virus (ISKNV). The phylogenetic tree was constructed based on neighbor-joining analyses of the MCP gene sequences, indicating that the pathogen in present study was a member of genusMegalocytivirus, named as tentativeSiganusfuscescensiridovirus (SFIV).
2014, Vol. 29 
