Record Details
Field | Value |
---|---|
Title | Control of furunculosis in Pacific salmon by immunization |
Names |
Overholser, Donald Lee
(creator) Fryer, J. L. (advisor) |
Date Issued | 1968-05-02 (iso8601) |
Note | Graduation date: 1968 |
Abstract | The purpose of this project was to study the possibility of controlling furunculosis in salmonid fish using immunological procedures. Antiserum with an agglutinating antibody titer of 1:20,480 against Aeromonas salmonicida was produced in a horse. This hyperimmune serum was used to passively immunize coho salmon, Oncorhynchus kitsutch, (jacks). However, this work was discontinued, because the experimental animals were infected with a protozoan parasite (Ceratomyxa shasta). Since a method of challenging the passive protection given adult coho jacks (Oncorhynchus kitsutch) was needed, a lethal dose of Aeromonas salmonicida cells was established. It was found that a 0. 2 ml injection (intramuscular) of Aeromonas salmonicida suspension giving 20 percent transmittance at 475 mμ would kill 60 percent of the test fish in 11 days. Four year old adult chinook were actively immunized with two vaccine preparations, each injected by two routes. It was found that vaccine in adjuvant preparation injected by the intramuscular route was most effective. All methods of immunization induced the formation of agglutinating antibody. However, the vaccine in adjuvant injected intramuscularly produced the highest titer (1:1, 280). An attempt was made to determine the optimal dose of vaccine in adjuvant when injected intramuscularly. No definite conclusion could be made, because most of the test fish died early in the experiment. Active immunization of juvenile coho salmon was attempted by orally administering two different vaccine preparations. The first vaccine employed was formalin- killed Aeromonas salmonicida cells. Practical protection of the test fish against a natural epizootic of furunculosis was not accomplished by feeding the animals this vaccine in the normal diet for 37 days. The total number of cells given 1,000 fish was 7.1x10¹⁴. The second vaccine was an alumprecipitated cell fraction of Aeromonas salmonicida. This preparation was also mixed with the normal diet (Oregon Moist Pellets) and administered at two levels, approximately 50 mg or 25 mg of vaccine per fish and at various time intervals before the epizootic. This alum precipitate was very effective for protecting the fish against a natural epizootic of furunculosis. Losses in two groups of fish which were not immunized were 27. 2 and 37.0 percent, while the highest loss in an immunized group was 0. 7 percent. The two levels of vaccine administered (25 mg or 50 mg) did not affect the degree of protection afforded the fish. The data indicated that protection could be given if vaccination was accomplished at least 27 days prior to the onset of the epizootic. |
Genre | Thesis/Dissertation |
Topic | Salmon -- Diseases |
Identifier | http://hdl.handle.net/1957/46817 |