Record Details
Viruses infecting salmonid fishes from Oregon : A. The occurrence and distribution of infectious pancreatic necrosis virus. B. The development of an attenuated strain of infectious hematopoietic necrosis virus (IHNV) for immunization of salmonids
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Viruses infecting salmonid fishes from Oregon : A. The occurrence and distribution of infectious pancreatic necrosis virus. B. The development of an attenuated strain of infectious hematopoietic necrosis virus (IHNV) for immunization of salmonids |
| Names |
Tebbit, Guy Lee
(creator) Fryer, J. L. (advisor) |
| Date Issued | 1975-09-22 (iso8601) |
| Note | Graduation date: 1976 |
| Abstract | The occurrence and distribution of fish viruses in Oregon were determined by the examination of anadromous and fresh water salmonids. Infectious pancreatic necrosis virus (IPNV) was isolated and identified from asymptomatic adult coho (Oncorhynchus kisutch) and chinook (0. tshawytscha) salmon returning to the Columbia River system. Infectious pancreatic necrosis virus was also identified as the causative agent of severe losses of eastern brook trout juveniles (Salvelinus fontinalis) at the Fall River trout hatchery in central Oregon. This was the first documented IPNV epizootic in fish from Oregon. A high incidence of IPNV was detected in eastern brook trout populations from central Oregon indicating that this virus poses a threat to the rearing of that species in Oregon. An attenuated strain of infectious hematopoietic necrosis virus (IHNV) was developed for use as a water-borne vaccine for the control of IHNV disease. This water-brone vaccine is easily administered as an immunizing agent by direct addition to the water containing fish. The attenuated IHNV water-borne vaccine strain was determined to be one hundred three times less virulent than the wild type strain from which it was derived. This vaccine was proven to be efficacious against high levels of both water route and injected challenges of virulent wild type virus in kokanee (0. nerka) and sockeye salmon (0. nerka). Other parameters for the development of an effective vaccine preparation were also tested. An optimal exposure period to the immunizing virus of 48 hours was determined as were the minimum immunizing dose for sockeye and chinook salmon. The attenuated IHNV water-borne vaccine produced immunity with a duration of at least 110 days and was shown to provide protection to sockeye salmon challenged with four isolates of virulent IHNV from different geographic locations. Another method of immunization, vacuum infiltration, was tested using a second strain of attenuated IHNV as an immunizing agent. Even though this method of immunization was effective in eliciting a protective immune response in chinook and kokanee salmon, it did not produce the level of protection provided by the attenuated IHNV water-borne vaccine. |
| Genre | Thesis/Dissertation |
| Topic | Salmonidae -- Diseases |
| Identifier | http://hdl.handle.net/1957/43312 |
