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C.K. Jenes

Publications and source records attributed to C.K. Jenes.

6 recordsLinked to original sources

Titre distribution patterns of infectious haematopoietic necrosis virus in ovarian fluids of hatchery and feral salmon populations

Infectious haematopoietic mecrosis virus (IHNV) is enzootic in virtually all populations of sockeye salmon, Oncorhynchus nerka (Walbaum), and in populations of chinook salmon, O. tshawytscha (Walbaum), of the Sacramento River drainage in California. This disease is an obstacle in hatcheries using brood stocks from these populations. However, naturally spawning sockeye salmon are highly successful and are the most important commercially fished salmon species in the United States. Most of the commercial landings of sockeye salmon are of feral fish originating in Alaska. The success of natural populations of salmon in which IHNV is enzootic, and the recurrent outbreaks of the disease in hatchery fish, led us to compare IHNW prevalence rates in hatchery and feral salmon populations.

Journal of Fish Diseases

Detection of infectious haematopoietic necrosis virus in river water and demonstration of waterborne transmission

In a study of the possible role of waterborne infectious haematopoietic necrosis virus in transmission of the disease among spawning sockeye salmon, Oncorhynchus nerka (Walbaum), both infection rates and virus titres were higher in fish held at high density in a side channel than in fish in the adjacent river. Virus was never isolated from river water, but was found in water from the side channel at levels ranging from 32.5 to 1600 plaque-forming units (p.f.u.)/ml. Uninfected yearling sockeye salmon held in a box in the side channel developed localized gill infections with IHN virus. The disease did not progress to the viscera until a threshold titre of about 10 5 p.f.u./g was reached in the gill. The effectiveness of the gill as a barrier limiting development of systemic infections means that waterborne IHN virus probably does not greatly increase the infection rate in a sockeye salmon population during spawning.

Journal of Fish Diseases

Appearance and quantification of infectious hematopoietic necrosis virus in female sockeye salmon ( Oncorhynchus nerka ) during their spawning migration

The incidence and amount of infectious hematopoietic necrosis (IHN) virus was determined in 10 organs and body fluids from each of 100 female sockeye salmon (Oncorhynchus nerka) before, during, and after their spawning migration into freshwater. Virus was found in high concentrations only in fish sampled during and after spawning. Infection rates increased from nil to 100 percent within 2 weeks. In spawning fish, incidences of IHN virus were high in all organs and fluids except brain and serum, and the highest concentrations were in the pyloric caeca and lower gut. Immediately before spawning, IHN virus was found most frequently in the gills, less frequently in the pyloric caeca and spleen, and rarely in other organs.

Archives of Virology

Comparison of in vitro growth characteristics of ten isolates of infectious hematopoietic necrosis virus

Ten isolates of infectious haematopoietic necrosis from salmonid fishes of different locations on the West Coast of North America from California to Alaska were compared by plaque size, single-step growth curves at 15 and 18 °C, rate of appearance of cytopathic effects in cell cultures, and growth over a range of temperatures. All isolates were distinguishable on the basis of each growth characteristic examined. The CO isolate from the Sacramento River drainage of California was the most singular of the 10 because of its diminutive plaque size and sensitivity to slightly elevated temperatures. The mean plaque diameter of the l0 isolates increased as the latitude of the geographic source of the isolate increased. Although the maximum titre obtained by all isolates was depressed at temperatures above approximately 18 °C, half of the isolates were not inhibited by temperatures as low as 0.5 °C. t.

Journal of General Virology

Mortality due to infectious hematopoietic necrosis of sockeye salmon ( Oncorhynchus nerk a) fry in streamside egg incubation boxes

Infectious hematopoietic necrosis virus caused mortality of sockeye salmon ( Oncorhynchus nerka ) in streamside egg incubation boxes. Virus was not detectable in eggs or alevins; its first isolation coincided with the appearance of dead fish in a trap on the outflow from the box. Mortality due to the virus did not occur in every egg box studied. However, when fry from the boxes were held in the laboratory, epizootics began as much as 3 wk later, with total mortality exceeding 90%. More than 96% of the dead fry had titers exceeding 10 5 plaque-forming units per gram. The peak incidence of virus in fry migrating in the river coincided with the arrival of hatchery-produced fry, although some fry believed to have been produced by natural spawning were also infected.Englis

Canadian Journal of Fisheries and Aquatic Sciences

Pathogenesis of infectious hematopoietic necrosis virus in adult sockeye salmon ( Oncorhynchus nerka )

The concentration of infectious hematopoietic necrosis (IHN) virus was determined in eight organs and two body fluids from each of 60 adult sockeye salmon ( Oncorhynchus nerka ). Included in the sample were 4 males and 56 prespawning, spawning, or spent female fish. All fish were infected, and virus was present in nearly all organs. There was an overall tendency for the mean concentration to increase in many of the organs over time as the fish progressed in ripeness. In prespawning females, IHN virus could be detected in all organs and in ovarian fluid but not in serum; the incidences were highest in the gills, spleen, and pyloric ceca, and the titers were highest in the pyloric ceca and liver. Incidences of infection in the organs were higher in spawning than in prespawning females and higher still in spent females in which the incidence of virus was 100% in all organs except brains (78%) and sera (67%). Virus concentrations in organs or fluids ranged from 5 to 4.0 × 10 9 plaque-forming units per millilitre. In males, the highest incidences of virus were found in gills, pyloric ceca, and liver. The gills were the only organ in which the virus concentration in males exceeded that of females. Key words : infectious hematopoietic necrosis, IHN, fish virus, viral pathogenesis, sockeye salmon

Canadian Journal of Fisheries and Aquatic Sciences