Three different levels of dietary vitamin D₃fed to first-feeding fry of Atlantic salmon (Salmo salarL.): effect on growth, mortality, calcium content and bone formation

Abstract

Atlantic salmon (Salmo salar L.) fry were reared on a fishmeal-based diet with three different levels of vitamin D 3 (0.2, 5 and 57 mg vitamin D 3 kg -1 feed, ww) from firstfeeding for 14 weeks. No significant differences were recorded in weight, length, specific growth rate, mortality, or kidney calcium concentration between the different dietary groups. No skeletal malformations or histopathological changes were recorded in any of the dietary groups. These results suggest Atlantic salmon fry to be highly tolerant of megadoses of vitamin D 3 over a limited period of time. KEY WORDS

Are we what we eat? Changes to the feed fatty acid composition of farmed salmon and its effects through the food chain

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