Jornal de Pesquisa e Desenvolvimento em Aquicultura

Abstrato

Partial Replacement of Plant Protein by Fish meal in the Diets of Nile Tilapia, Oreochromis niloticus (Linnaeus, 1758)

Egbal OA*, El-Nouman BA, Siham BM, Mona MA

Fishmeal is recognized by nutritionists as a high-quality, very digestible feed ingredient that is favored for addition to the diet of most farm animals, especially fish. In this study, plant protein was replaced by fish meal (FM) to determine the feasibility to the diets of juveniles of Nile tilapia fish Oreochromis niloticus. The experiment was conducted for 8 weeks in aquariums; each one was stocked with 15 fish of an average weight of 8.13 ± 1.3 g. The feeding trial was consisted of 4 treatments, first one without FM (control), the second, third and fourth a diet containing 4%, 8% and 12% FM respectively. The effect of each replacement level on the growth performance, feed utilization, and survival rate of the experimental fish was assessed. All the experimental diets were well accepted by the fish, and no mortality was observed during the experimental period. At the end of the experiment no different in survival rate, growth performance, across the dietary treatments (P ≥ 0.05) but the difference was significant (p ≤ 0.05) between control diet and the diet contain 12% FM. The percentage of the fish weight was 127.92 ± 3.57% for 12% FM diet, followed by 8% FM diet with 112.42 ± 3.34%, and then 4% FM diet with 103.29 ± 3.1%. The fish weight of the treatment without FM reached 80.44 ± 2.24%. The diet that contained 12% fishmeal is the best in terms of the rate of food conversion ratio (FCR) which recorded 2.60 ± 0.13, followed by 8% FM diet with 2.93 ± 0.16, and then 4% FM diet with 3.10 ± 0.17 and 3.78 ± 0.23for the diet without FM. The fish growth in the three treatments whose food contained FM was better than that of food did not contain it, despite containing the same protein content (35%). This indicates that fish meal improves the quality of protein, and the increase in growth was directly proportional to the increase in the percentage of FM in the diet.