Desempenho produtivo de três linhagens de tilápia-do-Nilo (Oreochromis niloticus) alimentadas com dois níveis de proteína

Abstract

This study aimed to evaluate the productive performance of three Nile tilapia (Oreochromis niloticus) lines, fed with two crude protein levels (25 and 30%). The lines studied were Bouaké (BOU), Chitralada (CHI) and GIFT. The fish were individually marked and housed in two land nurseries with 140 m2 each, in a completely randomized design using three lineages and two levels of crude protein, with each individual counting as one replication. The water quality remained appropriate for the species. With regard to the lines studied, GIFT had the best performance for weight gain and total length, height, final width and weight, fillet yield and weight, regardless of culture conditions. This superiority to nonimproved lines can be attributed to the breeding line. The tilapia fed with 25% CP exceeded in 51.0% (BOU), 47.0% (CHI) and 58.0% (GIF) the weight of those fed with 30% CP. The results suggest less need of CP for tilapia in the finishing phase and alert to the biological value of feed ingredients.