Effects of feeding a pigmented or non-pigmented diet to Arctic charr, Salvelinus alpinus, on flesh color and sexual maturity

Abstract

The objective of this study was to evaluate the effects of feeding pigmented feed (50 ppm astaxanthin) to diploid or triploid Arctic charr, Salvelinus alpinus, on growth rate, color of fillets, and the variability of color within fillets. Arctic charr with an average weight of 419.9 g±83.3 g, including both diploid (n=72) and triploid (n=72) fish, were allotted to each treatment: 0, 3 or 6 months of pigmented feed before slaughter. Color assessment was made using a portable reflected light colorimeter in the CIE 1976 L* a* b* color system mode. Feeding a pigmented diet to Arctic charr delayed sexual maturity in male Arctic charr and to a certain extent in females, but also slightly reduced the rate of growth. With increasing time on the pigmented diet, color parameters of the flesh increased as well as the variability in color. Triploid fish had more intense color assessments for each dietary treatment than the diploid fish.