Atratividade e palatabilidade de hidrolisado proteico de frango contendo substâncias coadjuvantes para alevinos de tilapia do Nilo (Oreochromisniloticus) e para o dourado (Salminus brasiliensis)

Abstract

This study was carried out with the aim of determining the attractiveness and palatability of diets containing chicken protein hydrolyzate with different supporting substances in comparison with a control diet in feed formulations, consisting of two experimental trials. Six diets containing: 1-fish meal ((FPE) - control diet); 2-hydrolyzed feather protein (PHP); 3-hydrolyzed chicken protein with 75% crude protein (CP) (PHF75%); 4-hydrolyzed chicken protein with starch (PHFA60%); 5-hydrolyzed chicken protein with yeast (PHFL60%); and 6-hydrolyzed chicken protein with maltodextrin (PHFM60%). In different experiments, fingerlings of Nile tilapia (Oreochromisniloticus) and goldfish (Salminus brasiliensis) were individually distributed in 12 aquariums with a useful volume of 20 liters each, with individual aeration and temperature control. The diets were provided six times a day, with prior random drawing being carried out, recommending the consumption of all diets at least once a day for each aquarium. The tilapia fingerlings weighing 6.48 ± 0.37g received 13 pellets at each feeding, while the goldfish fingerlings weighing 8.22 ± 0.89g received 6 pellets, according to the average consumption of the species, evaluated previously during the adaptation period. Filming was performed during three minutes, from the offer of experimental diets. The behaviors: time of capture of the first pellet, number of rejections, number of approaches without capture and number of pellets consumed were analyzed and after tabulated, the attractiveness and palatability index (IAP) was applied and submitted to ANOVA. In the tilapia assay, all tested diets showed positive IAP (above 85%) not differing from the control diet (p>0.05), demonstrating that they positively affect diet consumption. For the test with dorado, the tested diets showed a significant difference (p<0.05) regarding the attractiveness and palatability index (IAP). The PHF75% had the highest IAP (54.19%), while the control FPE diet had the lowest IAP (34.21%). Diets containing supporting substances demonstrated to interfere positively in terms of attractiveness and palatability for both species. The PHP diet was the one that presented the highest consumption of pellets for the test with tilapia (94.55%) and for the Dorado it was the PHF75% diet (61.83%).