Effect of Dietary Protease Supplementation on Growth, Hematology and Serum Biochemistry of African Catfish Fed Roasted Soybean-based Diet

Abstract

The African catfish (Clarias gariepinus) is also a good candidate species for culture to boost fish production for both domestic and global markets, which will improve human nutrition and food security in Africa. The study aims to investigate the effect of dietary protease on growth, haematology and serum biochemistry of African Catfish fed a roasted soybean-based diet. Six diets containing varied inclusion levels of protease (ppm) in roasted soybean-based diets were formulated as follows: PR0 (Control), PR100 (100), PR200 (200), PR300 (300), PR400 (400) and PR500 (500). Clarias gariepinus (C. gariepinus) juveniles (n=360) aged two months and weighing 12.04±0.19g were fed to satiation with the diets for 12 weeks. Each treatment was in triplicate. Final weight values showed that C. gariepinus fed diet PR400 (46.90±9.25) had significantly higher values with protease supplementation. Significantly, the lowest (P<0.05) values for feed conversion ratio were in C. gariepinus on PR400 (1.42±0.28) and higher in diet PR100 (2.75±0.59). Packed cell volume (%), haemoglobin (g/dL), red blood cell (x1012/L), white blood cell (x109/L), platelet (x109/L) and basophils (%) were unaffected (P>0.05) with supplemental protease in the diet. Total protein (%), albumin (g/L), globulin (g/L), AST (IU/L), and creatinine (µmol/L) were unaffected by protease supplementation in the diets. A-G ratio had a higher (P<0.05) value in C. gariepinus on diet PR400 (0.50±0.10). In conclusion, dietary protease supplementation at 400 mg/kg enhanced growth performance in C. gariepinus fed soybean-based diets, although its effects on haematological and biochemical indices were limited.