Effect of phytase supplemented moringa by-products based diets on the performance of oreochromis niloticus fingerlings

Abstract

Increasing human population and lower food availability motivated the researchers to search out the alternative and low cost feed sources for fish that is the basic protein source in human diet. For this purpose, study was performed to develop an eco-friendly and low-cost feed for ‘Nile tilapia’ fingerlings using Moringa derived products supplemented with phytase (PHY) enzyme. Moringa oleifera seed meal and leaf meal were used as the major components to make seven iso-nitrogenous and iso-caloric test diets (TD). These Moringa based test diets were developed by using different PHY levels (0 control, 500, 650, 800, 950, 1100 and 1250 FTU per kg). Seven groups (in three replicates) of tilapia fingerlings were fed at the rate of 4% of their live weight two times a day. After 70 days feeding trials, blood samples from each replicate were collected for the analysis of hemato-immunological parameters. Then these fish were sacrificed and dried for carcass analysis. After the application of one-way ANOVA, maximum retention of protein (18.26%) and fat (8.92) were found at 950 FTU per kg in comparison to other test diets. Study of hematological indices revealed that the maximal values of RBCs (2.92×106 mm-3), PLT (64) and Hb (8.19 g/100ml) were recorded at 950 FTU per kg level. Similarly, highest MCH, PCV, MCV and Ht. were also observed at 950 FTU per kg level. For the study of expression of growth genes, gel electrophoresis method was performed. It was concluded that PHY added diet at 950 FTU per kg showed maximum improvement in hemato-immunological parameters and body composition of tilapia with no side effects on fish health and non-differentiable results regarding growth gene expression.