Studies on pathogen of explosive epidemic disease of shrimp Ⅱ.Purification of pathogen

The pathogen of explosive epidemio disease of farmed Chinese shrimp(Penaeus chinensis)was isolated and purified from the cephalothorax and hepatopancreas of diseased shrimps by means of different speeds of centrifugation and sucrose gradient ultracentrifugation.The results showed that same virus isolated from the diseased shrimps in various regions of China was a kind of baculovirus covered with envelope,which was 95-125 nm in diameter and 360-410 nm in length.The size of the capsid was 80-90 nm×330-350 nm.The nucleic acid of the virus was demonstrated as DNA.The result of artificial infection demonstrated that the virus was the pathogen of explosive epidemic disease of farmed Chinese shrimp.