Growth response and physiological activities of the Nile tilapia (Oreochromis niloticus) fed basal diets supplemented with ginger (Zingiber officinale) as natural growth promoters

n experiment was conducted to evaluate the effect of two forms of dehydrated natural antioxidants rhizomes extracts ginger (Zingiber officinale) on growth performance feed utilization and hematological parameters
of Oreochromis niloticus fingerlings. Four treatments were applied, two forms of ginger (powder and oil extract), and their mixtures (1:1) of each form, in addition to control group were fed basal diets without supplements of herbs. The
experiment was conducted using cement ponds divided into four equal compartments each was stocked with 40 fingerlings oF Nile tilapia with an average initial body weight of 17.1 ± 1.2 g, and body length 10.0 ± 0.7 cm. The
experiment lasted for 12 weeks. Generally, growth performance, feed utilization ratios were improved for Nile tilapia (Oreochromis niloticus), fed on diets with the two forms of the feed supplements compared to fish fed on the control diet
All growth parameters in all supplemented groups increased significantly (P<0.05) as compared to the control group, especially for the fish fed on the mixture, with the highest survival rate. Incorporation of ginger extract improved
the antioxidant attributes and reduced quality degradation of test diets during storage at ambient conditions. In terms of liver and blood measurements, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine
aminotransferase (ALT) activities, these parameters decreased significantly (P<0.05) for fish fed on all treated groups with ginger. Plasma total protein, albumin and globulins of fish fed on the experimental diets significantly
increased (P<0.05) for those fed on the ginger, while blood glucose,triglycerides and cholesterol values were significantly decreased (P<0.05) in the same treated groups as compared to the control one. These results revealed that
the feeding with a mixture of ginger (powder and oil extract), can promote growth rate, decrease mortality rate and improve the physiological activities in reared fish, and can be potentially used as good sources of antioxidants.