Reducing Dietary Protein Content by Increasing Carbohydrates Is More Beneficial to the Growth, Antioxidative Capacity, Ion Transport, and Ammonia Excretion of Nile Tilapia (Oreochromis niloticus) under Long-Term Alkalinity Stress

Figure 1

Activities of MDA (a), CAT (b), SOD (c), and GSH-PX (d) in the liver of O. niloticus fed different dietary protein to carbohydrate ratios in freshwater or alkaline water for 50 days. All data are represented as the mean ± SEM (n = 6). Different letters in the same histogram show significant differences (). Indicates a significant difference between different alkalinity levels within the same diet protein–carbohydrate ratios (). Indicates a significant difference between different alkalinity levels within the same diet protein–carbohydrate ratios ().

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