DEVELOPMENT OF AN IN-VITRO QUANTAL ASSAY IN PRIMARY-CELL CULTURES FORA NON-OCCLUDED BACULO-LIKE VIRUS OF PENAEID SHRIMP

An in vitro quantal assay (TCID50) for a non-occluded baculo-like viru s isolate from naturally infected Penaeus japonicus obtained from Chin a and experimentally infected P. stylirostris was developed using prim ary shrimp lymphoid cell cultures in Primaria(TM) 24-well tissue cultu re plates. The virus caused cytopathogenic effect (CPE) in the cell cu ltures as early as 2 day post-infection (p.i.). Initially, the cells r ounded up and finally detached from the culture vessel as the infectio n progressed. At the present lime, there is no established quantitativ e in vitro cell culture protocol for the assay of this baculo-like vir us which has been reported by our laboratory to be highly pathogenic f or P. stylirostris and P. vannamei, the two species of penaeid shrimp commercially cultured in Hawaii and the Western hemisphere. This quant al assay thus provides a simple and convenient method for the detectio n and assay of infectious virus in cultured penaeid shrimp. Copyright (C) 1997 Elsevier Science B.V.