Fermented By-Products from Fruits as a Protein Source in the Basa Fish (Pangasius bocourti) Diets

Abstract

Four isonitrogenous and isocaloric experimental diets were developed to substitute soybean with fermented fruits wastes (FFWs), specifically fermented grape pomace (FGP), fermented apple peels (FAP), and a mixture of fermented grape pomace and apple peels (FGAPm) at a level of 25%. Four experimental groups, each comprising twenty-five basa fish (Pangasius bocourti, 7.5±0.5g), were maintained for twelve weeks with three repetitions per group. The growth performance, feed utilization, apparent digestibility coefficients (ADC), biochemical, enzymatic, and hematological characteristics of the fish were documented and assessed. Fish fed with 25% FGP exhibited considerably superior growth, survivability, and feed utilization in comparison with other experimented groups. The energy ADC of the FFWs diet exceeded that of the control. According to linear regression, basa fish (Pangasius bocourti) received 25% fishmeal, as a soybean protein substitute exhibited the maximum growth performance. FGAPm induced hyperglycemia, elevated plasma triglycerides, hepatic glycogen and albumin levels, enhanced alkaline protease and amylase activities, and reduced plasmatic proteins, cholesterol, and hepatopancreas AST levels. The dietary FGAPm caused a reduction of blood indices, alongside an elevation in erythrocytes counts. It was determined that fermented grape waste (FGP) can effectively substitute soybean protein by up to 25% regarding growth and feed efficiency.