Genetic Variation of Flesh Color in Pan-Size Rainbow Trout Fed Astaxanthin

Abstract

Flesh color was analyzed in 21 dam half-sib rainbow trout families (6 fish per family) that were fed a diet containing 100 mg astazanthin per kg feed. Physical color measurements (lightness, hue, and chroma) indicated that color levels induced by astaxanthin were under genetic control, the largest familial differences being obtained from lightness measurements. Lightness was found to be positively correlated with hue and with chroma. Before genetic programs can be developed to improve flesh color, measurement techniques should be optimized in terms of concordance with visual perception, and a selection index should be designed on the basis of consumer preference.