Green turtle fibropapillomatosis is a neoplastic disease of increasingly significant threat to the survivability of this species. Degenerate PCR primers that target highly conserved regions of genes encoding herpesvirus DNA polymerases were used to amplify a DNA sequence from fibropapillomas and fibromas from Hawaiian and Florida green turtles. All of the tumors tested (n = 23) were found to harbor viral DNA, whereas no viral DNA was detected in skin biopsies from tumor-negative turtles. The tissue distribution of the green turtle herpesvirus appears to be generally limited to tumors where viral DNA was found to accumulate at approximately two to five copies per cell and is occasionally detected, only by PCR, in some tissues normally associated with tumor development. In addition, herpesviral DNA was detected in fibropapillomas from two loggerhead and four olive ridley turtles. Nucleotide sequencing of a 483-bp fragment of the turtle herpesvirus DNA polymerase gene determined that the Florida green turtle and loggerhead turtle sequences are identical and differ from the Hawaiian green turtle sequence by five nucleotide changes, which results in two amino acid substitutions. The olive ridley sequence differs from the Florida and Hawaiian green turtle sequences by 15 and 16 nucleotide changes, respectively, resulting in four amino acid substitutions, three of which are unique to the olive ridley sequence. Our data suggest that these closely related turtle herpesviruses are intimately involved in the genesis of fibropapillomatosis.

Quantitative real-time PCR has been used to measure fibropapilloma-associated turtle herpesvirus (FPTHV) pol DNA loads in fibropapillomas, fibromas, and uninvolved tissues of green, loggerhead, and olive ridley turtles from Hawaii, Florida, Costa Rica, Australia, Mexico, and the West Indies. The viral DNA loads from tumors obtained from terminal animals were relatively homogeneous (range 2-20 copies/cell), whereas DNA copy numbers from biopsied tumors and skin of otherwise healthy turtles displayed a wide variation (range 0.001-170 copies/cell) and may reflect the stage of tumor development. FPTHV DNA loads in tumors were 2.5-4.5 logs higher than in uninvolved skin from the same animal regardless of geographic location, further implying a role for FPTHV in the etiology of fibropapillomatosis. Although FPTHV pol sequences amplified from tumors are highly related to each other, single signature amino acid substitutions distinguish the Australia/Hawaii, Mexico/Costa Rica, and Florida/Caribbean groups.

In May 2006 a large mortality of several thousand round gobies Neogobius melanostomus (Pallas, 1814) occurred in New York waters of the St. Lawrence River and Lake Ontario. Necropsies of sampled fish from these areas showed pallor of the liver and gills, and hemorrhagic areas in many organs. Histopathologic examination of affected tissues revealed areas of necrosis and hemorrhage. Inoculations of fathead minnow Pimephales promelas (Rafinesque, 1820) cell cultures with dilutions of tissue samples from the necropsied gobies produced a cytopathic effect within 5 d postinoculation. Samples of cell culture supernatant were tested using RT-PCR and confirmed the presence of viral hemorrhagic septicemia virus (VHSV). Sequence analysis of the VHSV isolate resulted in its assignment to the type-IVb subgroup. The detection of VHSV in a relatively recent invasive fish species in the Great Lakes and the potential impact of VHSV on the ecology and economy of the area will require further investigation and careful management considerations. KEY WORDS: Viral hemorrhagic septicemia · VHSV · Round goby · New York State Resale or republication not permitted without written consent of the publisherDis Aquat Org 76: [187][188][189][190][191][192] 2007 lege of Veterinary Medicine, Cornell University. The fish arrived at Cornell in moribund or freshly dead condition and were processed for diagnostic evaluation. The second sample consisted of 9 dead round gobies collected on 15 May 2006 from Sandy Creek, Lake Ontario, west of Rochester, New York. These fish were transported on ice to the AAHP at Cornell University.Cape Vincent, St. Lawrence River samples. All moribund fish were euthanized with an overdose of MS-222 (tricaine methanesulfonate, Western Chemical) in water. Eight fish were processed for diagnostic evaluation. The remaining 15 fish were frozen whole at -20°C for future evaluation if necessary. The procedure for diagnostic evaluation is described by Noga (1996) and included collecting skin scrapings and gill clip samples, sterile collection of posterior kidney samples for bacteriology, gross pathology and collection of tissues for histopathology and virology. Samples of liver, kidney, spleen and gonad were collected in 2 pooled samples for detection of viral agents. The first pooled sample (Sample A) included tissues from gobies that were dead at the time of presentation. The second pooled sample (Sample B) included fish that were moribund at the time of presentation. These samples collected for virus isolation were processed as described in the following sections. Attempts at bacterial isolation consisted of cultures taken from the posterior kidneys that were streaked onto blood agar (TSA II 5% SB, BBL™, Becton Dickinson). These cultures were incubated for 7 d at 21°C. Samples of intestines, gut contents and liver were collected to test additionally for type-E botulism by PCR (Getchell et al. 2006).Irondequoit Bay, Lake Ontario samples. Five fish were processed for diagnostic evaluation. Skin scrapings, gill ...

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