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Geology topics

W. J. Owens

Publications and source records attributed to W. J. Owens.

16 recordsLinked to original sources
USGS1994

Effects of elevated water temperature and immunosuppressant treatment on prevalence and titer of infectious pancreatic necrosis virus in naturally infected brook trout

Using fingerlings of brook trout Salvelinus fontinalis naturally infected with infectious pancreatic necrosis virus (IPNV), we demonstrated that elevated water temperature and treatment with the immunosuppressant triamcinolone acetonide (generic Kenalog®) significantly increases the titer of IPNV and probably also the prevalence of the infection. Stress-promoting treatments could potentially enhance the capability to detect various fish viral agents.

Journal of Aquatic Animal Health↗
USGS1992

Recovery of infectious pancreatic necrosis virus from the faeces of wild piscivorous birds

Faecal samples were collected from wild birds frequenting salmonid fish hatcheries to determine if birds excrete infectious pancreatic necrosis (IPN) virus in their faeces. Samples were collected from early June through early September. IPN virus was detected in faeces from herons, mallards, and other birds at titres similar to the titres found in the hatchery fish. Bird predation and virus prevalence in bird faeces was much reduced at a hatchery using electric fence barriers to deter birds and at a hatchery where the entire raceway area was enclosed by netting.

Aquaculture↗
USGS1986

Infectious pancreatic necrosis virus: Protocol for a standard challenge to brook trout

A protocol for experimental challenge with infectious pancreatic necrosis (IPN) virus was defined with brook trout Salvelinus fontinalis as the model species. Fish were exposed by immersion for 5 h in water containing IPN virus at a concentration of 10 5 plaque‐forming units per milliliter. We propose the protocol as a standard challenge based on our studies of exposure methods and host response to virulent virus. Immersion challenge induced higher and more consistent mortality than did challenge by hyperosmotic infiltration. Challenge virus should be sequentially transferred no more than five times in cell culture because further transfers reduced the virulence of the virus. At 12°C, mortalities due to primary infection occurred 6–12 d after immersion challenge and were highest (≥70%) in fish 27–56 d old. Susceptibility to lethal infection was enhanced by nutritional stress.

Transactions of the American Fisheries Society↗