Beneficial Changes in Growth Performance, Antioxidant Capacity, Immune Response, Hepatic Health, and Flesh Quality of Fed With .

The purpose of this study is to assess the feasibility of astaxanthin-rich as an immunostimulant in the diet for . Three experimental diets containing 0% (OC0), 1% (OC1), and 5% (OC5) . powder were formulated for 6-week feeding trials. The results indicated that the OC5 diet boosted the growth performance through decreasing the feed conversion ratio and increasing digestive enzyme activities and intestinal villus length. Meanwhile, fish fed with the OC5 diet promoted antioxidant ability stimulating the Nrf2-ARE signal pathway and enhancing antioxidant enzyme activities. Furthermore, the OC5 diet exerted hepatoprotective effects by suppressing the lipid deposition and inflammation response and enhancing the transport capacity of cholesterol. Besides, the OC5 diet improved the non-specific immunity by activating the lysozyme and complement system and increasing the nitric oxide content and total nitric oxide synthase activity. Dietary . supplementation promoted the deposition of astaxanthin in the whole body. Therefore, a diet supplemented with 5% . is recommended to boost the growth, antioxidant capacity, immune response, and flesh quality of .