Sodium taurocholate, a novel effective feed‐additive for promoting absorption and pigmentation of astaxanthin in blood parrot (Cichlasoma synspilum ♀ × Cichlasoma citrinellum ♂)

This study examined the effect of sodium taurocholate as a feed additive on the pigmentation efficacy of astaxanthin in blood parrot (Cichlasoma synspilum ♀ × Cichlasoma citrinellum ♂). A total of 396 fish were divided into six treatment groups with three replicates per treatment. The following experimental treatments were used: a basal diet (A) without astaxanthin; one diet (B) with 4‰ of astaxanthin; one diet (C) with only sodium taurocholate (600 mg/kg); and three diets with 4‰ astaxanthin plus sodium taurocholate (D, 400 mg/kg; E, 1200 mg/kg; F, 2000 mg/kg). Six fish per group were sampled at 15, 30 and 45 days. At the end of the experiment, the carotenoid content of the skin and the caudal fin in blood parrot fed with a supplementation of sodium taurocholate plus 4‰ astaxanthin was significantly higher than the corresponding values for the fish fed with 4‰ astaxanthin only (P < 0.05). The results demonstrated that sodium taurocholate is useful for promoting the absorption of astaxanthin and for promoting the pigmentation efficacy of blood parrot. This supplementation has potential applications for studying the color additives and formulated diets of ornamental fish.

► A novel effective feed-additive in blood parrot was found. ► Sodium taurocholate can improve the pigmenting efficacy of astaxanthin. ► Sodium taurocholate can enhance the physical fitness of ornamental fish. ► Sodium taurocholate can reduce feed costs and production promotion.