Journal of Fish Diseases lWO. 13, 557-560 SHORT COMMUNICATION Vibrio harveyi, an opportunistic pathogen of common snook, Centropomus undecimalis (Bloch), held in captivity T . K R A X B E R G E R - B E A T T Y & D. J. McGAREY Department of Biology and Institute for Biomolecular Scienee. University of South Elorida, Tampa. Elorida, USA H. J. GRIER Bureau of Marine Research. St Petersburg, Florida, USA D. V. LIM Department of Biology and Institute for Biomolecular Seienee, University of South Elorida, Tampa. Florida, USA Common snook, Centropomus undeeimalis (Bloch), is a gamefish classified as a protected species by the Florida Marine Fisheries Commission. In order to augment declining natural populations of common snook, the Florida Marine Research Institute (FMRI), Department of Natural Resources, St Petersburg, Florida, USA, has instituted a salt water enhancement programme, the goal of which is the release of hatchery-reared snook into Florida coastal waters. Potential eommon snook broodstoek were netted from Terra Ceia Bay, Manatee County, Florida and transported to FMRFs marine research facility in St Petersburg, Pinellas County. The fish were housed in 5000-gallon recirculating salt water fibreglass systems (Schieder 1984). Salinity was maintained at 32%o, salt water being made with artificial sea salts (Instant Ocean, Aquarium Systems Inc., Eastlake, OH, USA) with approximately 25% being replaced weekly. Dissolved oxygen ranged between 5 and 7 ppm, and temperature ranged between 28 and 30°C. Fish were fed frozen baitfish daily. As a result of probable abrasive damage during netting from Terra Ceia Bay, the corneas of numerous common snook began to turn opaque white within 24h of capture. Unless effectively treated with 0-1 ppm Prefuran (Argent Chemieal Laboratories, Redmond, WA, USA) in water, this ailment resulted in the fish becoming bhnd. Apparently, abrasion of the eye surface during capture targeted the eornea as a site of infection. Baeteria such as Aeromonas hydrophila, Edwardsiella ictaluri, Mycobacterium spp., Nocardia spp.. Streptococcus spp., and Yersinia ruekeri have been reported to cause oeular lesions in fish (Austin & Austin 1987). Vibrio spp. has caused opaque eyes in milkfish, Chanos chanos (Forskal) (Muroga, Lio-Po, Pitogo & Imada 1984). Previously documented evidence of piscine eye infections led to the investigation of baeterial involvement in the corneal pathology of the captive snook. Eyes from six aduh snook, ranging in size from 52 8 to 98'2cm fork length and 510g to 7 441kg, with opaque corneas were excised aseptieally after the fish were saerifieed by decapitation. The eyes were placed separately in sterile mortars and homogenized into a slurry with the addition of 2 5 ml of sterile 0-85% NaCl solution. Loopfuls of the homogenate were Correspondence: Dr Daniel V. Lim, Departcnt of Biology, Institute for Biomolecular Science, University of South Florida, Tampa, Horida 33620-5150, USA. 557