White spot syndrome virus in wild penaeid shrimp caught in coastal and offshore waters in the southern Atlantic Ocean

Abstract

White spot syndrome virus (WSSV) is a doublestranded rod-shaped DNA virus, which belongs to the family Nimaviridae, genus Whispovirus (Mayo 2002). Since its first appearance in 1992 (Chou et al. 1995), the disease has rapidly spread to different regions of the world with an economic impact approaching US$ 10 billion (OIE 2006). The first notification of WSSV in Brazil occurred in 2005 in Laguna–Santa Catarina, southern Brazil where the disease affected more than 1400 ha of shrimp ponds causing a production decline from 4189 tonnes in 2004 to 300 tonnes in 2007(Seiffert et al. 2006). Despite the lack of official records, it has been estimated that 90% of the shrimp industry in Santa Catarina collapsed in 2006 (Netto & Meurer 2006).In coastal waters of Brazil, there are no reports regarding the presence of WSSV in native wild shrimp. We therefore conducted research to evaluate the presence of WSSV in wild shrimps in the Laguna estuarine complex. In addition, wild shrimps were collected from offshore waters to evaluate the possible extent of virus dissemination. Thus, in February 2008, 750 wild juveniles of Farfantepenaeus paulensis (Pe´rez-Farfante) were captured in five sampling stations along the Laguna estuarine system (Fig. 1). One hundred and fifty Litopenaeus vannamei (Boone) were collected in a shrimp farm that operates a shrimp–tilapia polyculture. In addition, 420 F. paulensis were collected in October 2007 on the Santa Catarina coast (26º55¢ S, 48º11¢ W), 42 km from the shoreline.Some of these animals died during the collecting trip and presented a white colour of the posterior somites. Two hundred and fifty Farfantepenaeus brasiliensis (Latreille) were caught further North in January 2009 (26º16¢S 48º10¢W) and ca 36 km from the coast.