Amelioration of growth, blood physiology and water quality by exogenous dietary supplementation of pepsin in striped catfish, Pangasianodon hypophthalmus

Abstract

Digestive enzymes are the key regulators in the assimilation and metabolism of food intake. Multiple enzymes, amino acids and probiotics have been established in the food utilisation and physiological processes in many animal groups, while physiological data on pepsin, a proteolytic enzyme, are still lacking. Therefore, the aim of this study was to evaluate the dietary supplementation with pepsin for striped catfish (Pangasianodon hypophthalmus), a commercially important aquaculture species. Four pepsin-supplemented diets were tested (0, 0.25, 0.50 and 1.00 g/kg) for a period of 90 days. Results showed that dietary supplementation with pepsin at 0.50 g/kg diet improved significantly (p ˂ 0.05) the growth performance (higher weight gain and specific growth rate), feed utilisation (better feed conversion ratio), blood physiology (increased red blood cell and white blood cell counts and haemoglobin and haematocrit levels) and water quality (lower ammonia, nitrate and nitrite levels) in the striped catfish culture by better utilisation of protein compared to the non-pepsin diets. The present results indicate that supplementation with pepsin can improve the production performance of striped catfish and thus be applicable in commercial aquaculture.