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Elaboration d’aliments composés secs pour le Tilapia du Nil, Oreochromis niloticus (L., 1758) en élevage dans les eaux géothermales du sud tunisien

Bull Inst Nat Sci Tech Mer 01/2005; 32:56-67.

ABSTRACT Dans le but de promouvoir l’alimentation du Tilapia en élevage dans les fermes aquacoles tunisiennes, quatre aliments composés secs ont été élaborés à partir de matières premières conventionnelles et contenant différents taux de farine de poisson de fabrication locale (0 %, 10%, 20 % et 30 %). Ces aliments composés, de 36 % de protéines brutes et 6 % de lipides, ont été testés sur des alevins de Tilapia de poids moyen initial de 2 g. Après 45 jours d’expérimentation, les poids moyens finaux ont varié entre 21,33 g et 29,34 g selon les traitements. Les meilleurs taux de croissance et de transformation alimentaire ont été obtenus par les aliments contenant 20 % et 30 % de farine de poisson, avec des taux de croissance spécifiques (TCS) respectifs de 5,82 % et 5,89 % et des taux de conversion de 1,71 et 1,49, contre un TCS de 5,2 % et un TC de 1,96 obtenus avec l’aliment témoin. Ce test qui nous a permis de disposer d’aliments performants pour le prégrossissement du Tilapia sera poursuivi pour la valorisation des sous produits agroalimentaires locaux dans l’alimentation de ce poisson.

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