Effect of varied levels of dietary protein and lipid on growth response, nutrient utilization, and whole body composition of climbing perch, Anabas testudineus (Bloch, 1792) fry

This study investigated the effects of varying dietary protein and lipid levels on the growth performance and whole-body composition of climbing perch (Anabas testudineus) fry. Fish (initial weight: 0.34 +/- 0.01 g) were fed nine semi-purified diets with three protein (35%, 40%, and 45%) and three lipids (6%, 8%, and 10%) levels for 60 days. While survival rates were unaffected by dietary treatments, fish fed a diet containing 40% protein and 8% lipid exhibited significantly higher (P < 0.05) weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), and protein productive value (PPV), and lower feed conversion ratio (FCR) compared to other groups. Dietary protein and lipid levels had significantly (P < 0.05) affected whole-body composition. Second-order polynomial regression analysis showed that the optimal dietary protein and lipid requirements for climbing perch fry are in the ranges of 40.54-40.68% and 8.17-8.30%, respectively. These findings provide valuable insights for formulating nutritionally balanced diets to support optimal growth and development of A. testudineus fry.