Effects of Pomegranate (Punica granatum) Peel Methanolic Extract Dietary Supplementation on Oreochromis Niloticus Performance, Blood Health, Intestine Morphometry and Immunity

Abstract

This study evaluated the dietary pomegranate peel extract (PPE) effects on performance, blood health, intestine morphometry and Aeromonas hydrophila resistance of monosex Nile tilapia (Oreochromis niloticus). Fish (n=120, 9.5±0.5 g) were randomly distributed into four equal triplicate groups. A basal diet supplemented with PPE at a rate of P0, 0.05, 0.1 and 0.3 % representing P0 (control group), P0.05%, P0.1% and P0.3% groups respectively. Fish were fed diets 2 times daily for 70 days at a rate of 4% of fish body weight. The P0 and P0.05% showed significantly (P<0.05) improved growth performance (final weight, weight gain and feed conversion ratio) in respect to P0.1% and P0.3%. Fish that received PPE showed significantly (P<0.05) higher haematological assay (RBCs, WBCs, lymphocyte, and monocyte) compared to P0. A significant (P<0.05) increase in total protein, globulin, albumin and decrease in aspartate aminotransferase, alanine aminotransferase, urea, uric acid, creatinine, triglycerides, and cholesterol was reported in fish received PPE compared to P0. Immune response (higher lysozyme activity, phagocytic activity, phagocytic index, and immunoglobulin M), oxidative/antioxidant status (higher superoxide dismutase activity and lower malondialdehyde level) and intestinal morphometry (higher goblet cell number and villi length) were significantly (P<0.05) higher in fish received PPE in respect to P0 in a dose dependent manner. Fish received PPE showed low mortality rate through achieving the highest protection against Aeromonas hydrophila infection compared to P0. In conclusion, PPE dietary supplementation improved blood health, intestine morphometry and immunity of Nile tilapia while inducing an improvement in fish performance in P0.05 group.