Effect of Spirulina platensis as feed supplement on growth performance, immune response and antioxidant status of mono-sex Nile Tilapia (Oreochromis niloticus)

To evaluate the effect of Spirulina platensis inclusion in diets for Nile tilapia fingerlings, a completelyrandomized experimental design was developed with 4 treatments and three replicates. Diets with 4inclusion levels (control diet (Sp0), 0.5% (Sp0.5), 1% (Sp1) and 1.5% (Sp1.5)) were prepared. 180 Niletilapia fingerlings with average initial weight of 8.46±0.17 g were assigned to twelve experimental tanks.The experiment lasted for ten weeks. At the end of the experiment; growth performance, the whole bodycomposition was determined and serum samples for lysozyme, IgG, IgM values and catalase activitywere collected and antioxidant status of Nile tilapia muscle were determined. The results showed thatgroup supplemented with 1% S. Platensis have higher body weight and lower FCR than the controlgroup and other groups. S. platensis inclusion increased activity of glutathione reductase, and reduceMDA formation. Levels of lysozyme, IgG and catalase activity were higher in S. platensis supplementedgroups but don’t have significant effect on IgM level. In conclusion, Spirulina platensis supplementationincreased antioxidant protective capacities. It also affected some innate and humoral immunityparameters as well as don’t have negative effect on fish growth