Abstract
This study was conducted to investigate the effect of lysine supplementation on the growth performance, body composition and haematological characteristics of Clarias gariepinus juveniles in a plant protein-based diet. Juvenile fish (n=270), weighing 4.47±0.04g were randomly allocated to six diets containing varied inclusion of lysine (g/100g) in the formulated basal plant protein-based diets as follows: T0 (Control diet without lysine supplementation), T1, T2, T3, T4 and T5 containing 0.2 g, 0.4 g, 0.6 g, 0.8 g, and 1.0 g of lysine, respectively. The fish were fed to satiation for 8 weeks. Each treatment was in triplicate. The dietary supplementation of 0.6g/100g (T3) of lysine significantly (p<0.05) increased the weight gain of C. gariepinus compared to other treatments. No significant difference (p>0.05) were observed in the values for feed conversion ratio and the values ranged from 2.60±0.89 (T3) to 5.73±2.89 (T2). Supplementation of lysine in diets significantly (p<0.05) improved packed cell volume (PCV) as inclusion levels increases with the higher value in T5 (19.67±5.77) and least in control diet (7.33±3.51). No significant difference (p>0.05) were observed in White blood cell (WBC) values among the fish fed supplemental lysine however, they were significantly (p<0.05) higher than the control. Significant (p<0.05) increase was observed in crude protein values as the level of lysine increases up to T4 (71.10±0.33) and least in control diet (53.60±0.26). The least ether extract value was recorded in fish fed diet T3 and T4 (7.20±0.10). This study has showed that supplementation of lysine at 0.6g/100g in plant protein-based diet has the potential to improve growth performance, enhance better health condition and increase protein deposition in C.gariepinus