The effect of astaxanthin in feed and environmental temperature on carotenoid concentration in the gonads of the green sea urchin Strongylocentrotus droebachiensis Muller

The aim of this study was to investigate the long term development of carot enoid concentration in gonads and gonad development of green sea urchins re ared at different temperatures and fed formulated feed containing different levels of astaxanthin, Urchins, sampled from a natural population, were re ared under two different temperature regimes (7 C and 12 C) and fed formula ted feed containing 0, 100 and 500 mg astaxanthin/kg feed, respectively, Th e study lasted 112 d, Astaxanthin was detected in the groups fed feed conta ining astaxanthin, but in low quantities. No effect of temperature was obse rved on the retention of astaxanthin, Echinenone values declined throughout the study, probably due to the lack of suitable metabolic precursor for pr oduction of echinenone, Water and lipid concentration in the gonads increas ed throughout the study indicating the progressions of gametogenesis and th e generally improved nutritional status of the animals, No significant diff erence in gonad index (GI) due to treatment was observed but GI varied betw een the sexes with male GI increasing significantly faster compared to fema les.