Atratividade e palatabilidade da proteína hidrolisada de penas de aves com diferentes níveis de sulfito em rações para alevinos de tilápia do Nilo (Oreochromis niloticus)

Abstract

The present study aimed to evaluate the attractiveness and palatability of six diets containing different levels of hydrolyzed feather protein, with and without sulfite addition, for Nile tilapia (Oreochromis niloticus) juveniles. The formulations tested were: SFPE (negative control, with 2% feather meal), FPE (positive control, with 2% fish meal), PHP1%S (1% hydrolyzed feather protein without sulfite), PHP2%S (2% hydrolyzed feather protein without sulfite), PHP1%C (1% hydrolyzed feather protein with sulfite), and PHP2%C (2% hydrolyzed feather protein with sulfite). Twelve juveniles (7.38 ± 0.20 g) were distributed in 20-liter aquaria and fed six times per day with 0.1889 g per feeding (35 pellets), following a completely randomized experimental design. Feeding behavior was recorded via video for three minutes during each feeding session, analyzing the following parameters: time to first pellet capture, number of rejections after capture, intake (number of pellets consumed), and time spent feeding. A significant difference was observed at 8:00 h for the attractiveness and palatability index (API) and pellet rejections after capture, while no significant differences were found for the other time points and parameters (p > 0.05). Therefore, it can be concluded that the tested diets exhibit attractiveness and palatability comparable to the control diets and may be considered for inclusion in diets for Nile tilapia.