Abstract:
The present study was conducted to investigate the effects of CoQ10 dietary supplementation on growth per formance, feed utilization, blood profile, immune response, and oxidative status of Nile tilapia (12.4 ± 0.11 g,
initial body weight). Five experimental diets were formulated containing CoQ10 at levels of 0, 10, 20, 30,
40 mg kg−1 diet (D1, D2, D3, D4, and D5, respectively). The results of a 56-days feeding trial showed that,
significantly higher weight gain % (WG %), specific growth rate (SGR), feed intake (FI), and feed efficiency ratio
(FER) were recorded in fish groups fed diets supplemented with different levels of CoQ10 than fish fed the
control diet, while survival rate (SR%), condition factor (CF), hepatosomatic index (HSI) and viscerasomatic
index (VSI) showed no obvious differences (P > 0.05) among all experimental groups. The highest activities of
digestive enzymes (protease, amylase, and lipase) were recorded in D3, D4, and D5 groups. Moreover, blood
status of all experimental fish was within normal rates and significant alterations were only in the case of
glucose, cortisol, total cholesterol (T-Chol), triglycerides, and total protein (TP), where fish fed on D3, D4 and D5
diets exhibited lower values of glucose, cortisol, T-Chol, and triglycerides and higher values of TP. Furthermore,
the lowest values of immune response [lysozyme, bactericidal, respiratory burst (NBT), and alternative com plement pathway activities (ACP)], antioxidant capacity and oxidative related genes expressions [superoxide
dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX)] resulted from feeding on the basal diet (D1)
compared to CoQ10 diets, especially with its high levels {≥20 mg kg−1 diet (D3, D4, and D5)} in most cases. In
conclusion, our results suggest that the use of ≥20 mg CoQ10 kg-1 diet improves the growth and health being of
Nile tilapia.