Effect of Lemna gibba and Ulva lactuca on health and productive performance in juveniles of Nile tilapia (Oreochromis niloticus)

Abstract

Currently, mannan-oligosaccharides (MOS) are added to the production costs of Nile tilapia to prevent and avoid diseases. An alternative are aquatic plants rich in biologically active compounds such as Lemna gibba, a freshwater macrophyte, and Ulva lactuca, a green seaweed, which have shown productive and economic efficiency as feed for livestock, poultry, and fish, but their effect as a functional ingredient has not been evaluated. The objective was to demonstrate that dietary supplementation of juvenile Nile tilapia (Oreochromis niloticus) with L. gibba and U. lactuca can have a beneficial effect on the health and productive performance of tilapia allowing to consider these supplements as functional ingredients such as mannan-oligosaccharides (MOS). The base diet was supplemented with L. gibba and U. lactuca at percentages 0, 10, 15 and 20 % (L0, L10, L15, L20; U0, U10, U15, U20; M0, M10, M15, M20) and compared to a mannan-oligosaccharide (MOS) control. Health parameters (hematological study, lysozyme and complement C3 activities) and productive performance (survival, S; final weight, FW; protein efficiency ratio, PER, and feed conversion factor, FCF) were evaluated. Statistical difference was found (p ≤ 0.05) among treatments and supplementation percentages. The U20 diet showed the greatest effect (p ≤ 0.05) on health parameters and L15 showed the best results (p ≤ 0.05) in productive performance. It is concluded that U. lactuca and L. gibba can be used as a functional ingredient at a proportion of 15 % to produce feed for Nile tilapia juveniles in order to promote health and growth.