Efficacy of Astaxanthin Fed to Rainbow Trout (Oncorhynchus mykiss): Effect on Growth, Pigmentation and Blood Indices

In this study, the effect of astaxanthin on growth, pigmentation and blood factors were studied in rainbow trout weighted average (93±0.64 g) for 8 weeks. Two treatments and three replicates were employed as follows: Treatment A: fed with a commercial diet (control), treatment B: 41 mg/kg astaxanthin. All treatments were fed in hours 8, 12, 16, respectively. It should be considered that the feeding rate of biomass weight was examined after each took biometrics. Finally, blood samples were taken from the fish. The results revealed a significant difference between treatments in terms of weight and length (p<0.05) and no significant difference (p>0.05) in food intake and growth performance parameters, including FCR, SGR, GR, BWI%, and survival rate between treatments. In terms of pigmentation between experimental treatments, astaxanthin was created more change color than the control group. Results of blood factors showed that between WBC, RBC, Hb, HCT, Lymphocytes, Neutrophils, Monocytes and IgM were significant differences between treatments (p<0.05). So we can conclude that 41mg/kg astaxanthin dietary, due to economy, would be proper diet in the feeding of rainbow trout propagation.