PROPHYLACTIC TREATMENT OF VIRAL DISEASES IN FISH USING NATIVE RNA LINKED TO SOLUBLE AND CORPUSCULAR CARRIERS

The potential of double- (ds) and single-stranded (ss) yeast RNA prepa rations for protection of carp Cyprinus carpio against experimental in fection with Rhabdovirus carpio, the infectious agent of spring viraem ia of carp, was studied. Prophylactic intraperitoneal injection of fis h with dsRNA proved efficient while ssRNA had a much smaller effect. T he protective effect of yeast dsRNA in 1-year-old carp lasted for at l east 3 weeks. The efficacy of the preparations decreased considerably if they were administered by the bath method. Both insoluble and solub le carriers for dsRNA were studied to increase the preparation efficac y. Screening of the preparations revealed the importance of DEAE-group s on the carriers. Their biological efficiency is confirmed by the met hod of phagocytosis of the mouse peritoneal macrophages. (C) 1996 The Fisheries Society of the British Isles