Apparent digestibility coefficient of chitosan foam for nile tilapia

Abstract

Chitosan foam can be used as a filter element for pollutants in Nile tilapia farming tanks to reduce the industrial chitin waste and value it. Another possibility is the inclusion of chitosan foam in fish feed. Therefore, this study aims at evaluating the apparent digestibility of nutrients and energy of chitosan foam for Nile tilapia. Apparent digestibility determination was carried out by the indirect fecal collection method, using chromic oxide as an inert indicator, a reference-diet and a test diet (70% reference-diet and 30% chitosan foam). Hence, 120 juveniles of Nile tilapia (50 ± 5 g) were used, divided into six replications. After the collection period, bromatological analyses of foam, diets and feces were carried out, as well as the determination of chromium concentration in feces. The coefficients of apparent digestibility concerning nutrients and energy were then calculated. Chitosan foam showed 83.7% digestible dry matter, 5.7% digestible protein, 7.9% digestible fat, 0.6% digestible ashes, 17.6% digestible crude fiber and 1021 kcal kg -1 digestible energy for juveniles of Nile tilapia. It can be concluded that chitosan foam is partially digestible for Nile tilapia and can be used mainly as a feed source of fiber and fat.