Presence of the two viral pathogens WSSV and MBV in three wild shrimp species (Penaeus indicus, Metapenaeus ensis and Metapenaeus lysianassa) cultured in the mangrove forest of Ca Mau Province
Hao, N. V., Thuy, D. T., Loan, L. T. T., Phi, T. T., Phuoc, L. H., Duong, H. H. T., Corsin, F. and Chanratchakool, P.
Asian Fisheries Sci.
The aim of this research was to determine the presence of the two viral pathogens White Spot Syndrome Virus (WSSV) and Monodon Baculovirus (MBV) in three wild shrimp species (Penaeus indicus, Metapenaeus ensis, M. lysianassa) cultured in the mangrove forest of Ca Mau Province (Viet Nam) by using Polymerase Chain Reaction (PCR) and histological techniques. The study also sought to determine the season during which mass mortality occurs more frequently, the correlation between the presence of WSSV and MBV and some main water quality parameters of the mangrove in both mixed and separate models. The results of this research show that WSSV was simultaneously present in wild shrimp seeds and Acetes spp. during January, April, and May while MBV was present all year round. Pathogen was detected more often in the separate model. WSSV was present in shrimp at harvest in most of the samples, especially in the ones collected during the rainy season and in the middle of the dry season. MBV at harvest appeared throughout the whole year with a higher prevalence during the rainy season. Mass mortality occurred four times during the sampling period (i.e. January, June, July and October). This phenomenon was associated with the presence of WSSV at high prevalence and intensity. Some recommendations to reduce the risk factors of mass mortality are also presented.