THE EFFECT OF DIETARY Moringa oleifera FLOWER EXTRACT ON GROWTH AND ANTIOXIDATIVE ENZYMES ACTIVITY OF NILE TILAPIA Oreochromis niloticus  

Esayas Welday Tekle1,2 ,  N.P. Sahu*, P. P1. Srivastava and Muralidhar P. Ande3
 
1 Central Institute of Fisheries Education, Yari Road, Versova, Mumbai-400061, India
2 Massawa College of Marine Sciences and Technology, P. O. Box 8451 Asmara, Eritrea, e_welday@yahoo.com
3 Kakinada Centre, Central Institute of Fisheries Education, Kakinada, India
 

A stressful water environment in intensive aquaculture systems together with the respiratory burst activity of the immune cells leads to the generation of excessive reactive oxygen species (ROS) that alter the biochemical processes and enzymatic activities of the organism, ultimately causing oxidative damage to the body cells. Superoxide dismutase (SOD) and catalase (CAT) are the primary indicators of oxidative stress and cell damage when the culture species is exposed to certain stress factors. Growth performance and disease resistance conditions of fish are direct reflections of the metabolic alterations in the biological system of the body. Plant and herbal extracts are nowadays considered to be safe and natural antioxidants as well as immune-modulators against stress and diseases. Moringa oleifera is amongst the well-known medicinal plants with enormous ameliorating effects against stress-related diseases.

A 60-days trial was conducted to evaluate the effect of ethanolic extract of Moringa oleifera flower on growth performance and enzyme activities of Nile tilapia fingerlings. Four isocaloric and isonitrogenous purified diets were formulated with graded level of ehtanolic flower extract (EF) viz. 0% (control), 0.25% (EF.25), 0.5% (EF.5) and 1% (EF1). Fish (8.78±1.36g) held in 120 l plastic tanks, in triplicate, were fed ad lib twice daily.

After 60 days growth period, fish group fed on the diet EF.25 as compared to the control or the other treatment groups exhibited significantly higher (P < 0.05) weight gain, energy and protein retention, protein efficiency ratio (PER), specific growth rate (SGR) and CAT activity as well as lower FCR and SOD activity. Thus, Nile tilapia diets supplemented with ethanolic extract of M. oleifera flower at 0.25% inclusion level appears to be helpful in modulating the immune status of the fish and hence improve the disease resistance and growth performance.