Aquaculture: 1997 Publications

Author: Garza, J.R., Hasson, K.W., Poulos, B.T., Redman, R.M., White, B.L., and Lightner, D.V.
Title: Demonstration of infectious Taura syndrome virus in the feces of seagulls collected during an epizootic in Texas.
Publication: Journal of Aquatic Animal Health 9(2):156-159, 1997.
© American Fisheries Society

Notes : Laughing gulls Larus atricilla were observed feeding on diseased shrimp Penaeus vannamei during an epizootic of the Taura syndrome virus (TSV) at a south Texas farm in May 1995. Fresh fecal samples were collected from a gull roosting site on a pond lever where gulls that fed on diseased shrimp had roosted overnight. The feces samples were tested for the presence of TSV by injection bioassay. A cell-free clarified homogenate of the fecal material was injected into indicator P. vannamei, and the shrimp were observed for 9 d. Cumulative mortalities of the two replicate groups of indicator shrimp were 45% and 70%. Moribund indicator shrimp collected and preserved for histological examination exhibited lesions pathognomonic for acute-phase infections by TSV. The presence of TSV in the induced lesions was confirmed with in situ hybridization with cDNA probes specific for a portion of the TSV genome. The presence of infectious TSV in the gulls' feces supports the hypothesis that these birds are a probable transport vector of the virus within and among nearby shrimp farms.