Evaluation of cuttlefish protein hydrolysate as partial fishmeal replacement in diet for tilapia (Oreochromis niloticus) fingerlings: Influence on growth and disease resistance

Abstract

With global fishmeal production declining, this study valorised cuttlefish processing waste into cuttlefish protein hydrolysate (CFPH) as a sustainable aquafeed ingredient. Generally, protein hydrolysates enhance growth performance and immunity in fish, the optimal CFPH level for fish and its influence on growth and disease resistance efficiency remain unstudied - a gap this research addresses while valorizing fishery by products. With this background, the present study was designed to evaluate the effects of dietary CFPH as a partial fishmeal replacement on growth performance and disease resistance in tilapia (Oreochromis niloticus) fingerlings. During the feeding trial, animals were fed with isonitrogenous and isocaloric diets such as Control (0 g CFPH & 20 g FM/100 g), T1 (5 g CFPH & 15 g FM/100 g), T2 (10 g CFPH & 10 g FM/100 g), T3(15 g CFPH & 5 g FM/100 g), T4(20 g CFPH & 0 g FM /100 g), T5(0 g CFPH & 0 g FM/100 g) for a period of 65days. Fishes fed with the diet containing 15 g CFPH/100 g diet showed significantly (P < 0.05) improved weight gain percentage, specific growth rate, protein efficiency ratio and feed conversion ratio compared to control diets. Whereas, increasing the inclusion of CFPH in diet beyond 15 g/100 g negatively affected the growth performance of tilapia fingerlings. After the feeding trial, fishes were subjected to a challenge study with Aeromonas hydrophila, treatment group fed with diet containing 20 g CFPH/ 100 g diet showed significant (P < 0.05) defensive efficiency against the virulent bacterial infection. Based on the outcome of the present study, it is concluded that CFPH is one the potential aqua-feed ingredients having both the growth performance and diseases resistance efficiency.