Record Details
Field | Value |
---|---|
Title | The heritability of resistance to gas bubble disease of Columbia River fall Chinook salmon, (Oncorhynchus tshawytscha) |
Names |
Cramer, Steven P.
(creator) McIntyre, John D. (advisor) |
Date Issued | 1974-05-09 (iso8601) |
Note | Graduation date: 1974 |
Abstract | A nested mating experiment in which 20 males were each mated to four different females was used to obtain an estimate of the heritability of resistance to death from gas bubble disease in Columbia River fall chinook salmon (Oncorhynchus tshawytscha). Heritability estimates ranged from 0. 037 to 0. 038. Bioassays in 127 percent air supersaturated water were used to compare the inherent resistance to gas bubble disease of selected Columbia and Trask River stocks of juvenile fall chinook salmon. In the first of two comparative bioassays, time to 50 percent mortality in offspring from adults obtained at Little Goose Dam on the Snake River was more than twice as great as that in offspring from adults obtained from the Trask River. In the second experiment, no significant difference in resistance to death from gas bubble disease was found among several lower Columbia River stocks of fall chinook; however, the average resistance of these stocks was significantly greater than that of Trask River fall chinook. A population model which incorporated response to selection for increased resistance to gas bubble disease was used to predict the numbers of fall chinook returning in the future to Kalama Hatchery. It was found that smolt survival can be expected to show a maximum increase of five to ten percent after 30 years of selection. These results indicated that gas bubble disease will remain as a major source of mortality of fall chinook smolts in the Columbia River until lethal levels of air supersaturation are eliminated. |
Genre | Thesis/Dissertation |
Topic | Salmon -- Diseases |
Identifier | http://hdl.handle.net/1957/22162 |