Submitted to: Aquaculture Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2003
Publication Date: 3/7/2004
Citation: Welker, T.L., James, C.L. 2004. Relationship between dietary lipid source, oxidative stress, and the physiological response to stress in sub-yearling chinook salmon (oncorhynchus tshawytscha). Aquaculture Conference Proceedings.
Technical Abstract: Relationships between dietary lipid source, stress, and oxidative stress were examined in juvenile chinook salmon. Four different experimental diets were used: menhaden oil (MHO; elevated 20:5n-3 and 22:6n-3), soybean oil (SOY; elevated 18:2n-6), linseed oil (LSO; elevated 18:3n-3), and a mixture of 55% linseed oil and 45% soybean oil (MIX; approximately equal levels of 18:2n-6 and 18:3n-3). Fish subjected to a low-water stressor had greater liver and brain lipid peroxidation compared to unstressed controls; peroxidation was not influenced by diet. Diet and stress affected plasma cortisol levels. Stressed fish fed SOY had the greatest cortisol concentrations, followed by MIX, MHO, and LSO (mean concentrations for the SOY and LSO diets differed significantly). The cortisol response to stress may have been influenced by the ratio of prostaglandin 1- and 2-series to prostaglandin 3-series precursor fatty acids provided by the different diets. The results of this study suggest a connection between the physiological response to stress, dietary lipid quality, and oxidative stress. This is the first evidence of such a relationship in fish.