The current study investigated the effects of Moringa (Moringa oleifera) leaf meal (MLM) on growth and
stress indices of Nile tilapia (O. niloticus). Experimental fish (2.0 ± 0.5 g average body weight) were
divided into two groups; one was fed with a diet not supplemented with MLM (control diet), and the
other group was fed with a diet supplemented with 1.5% MLM (diet 2) for three-month period. The results
showed that MLM incorporation in the diet improved growth indices (body mass gain, specific growth
rate, length gain rate and feed conversion ratio) and somatic indices (spleen somatic index, hepatosomatic
index and intestine somatic index). Moreover, all hematological indices were also significantly
increased. Additionally, stress indices were significantly improved, including antioxidants; superoxide
dismutase, glutathione peroxidase, catalase and lipid peroxidase; and biochemical indices including
enzymes activities of Aspartate Aminotransferase and Alanine Transaminase, as well as glucose and cortisol
concentrations. Also, markedly up-regulated the expression of related genes; Insulin-Like Growth
Factor-1 (IGF-1), Transforming Growth Factor-b (TGF-b) and superoxide dismutase (SOD) genes; in fish
group fed diet supplemented with MFM as compared with the control group. These results show that
MLM effectively alleviated starvation stress through retaining the enhanced growth and stress indices.
In conclusion, Moringa supplementation to Nile tilapia has a positive effect as growth promoter and natural
anti-stress phyto-therapy.