Influência da densidade de estocagem na composição química, no colesterol e no perfil de ácidos graxos em Tilápia do Nilo (Oreochromis niloticus LINNAEUS, 1857) Influence of stocking density on the chemical composition in cholesterol and fatty acids profile in Nile Tilapia (Oreochromis niloticus LINNAEUS, 1857)

To assess the infl uence of stocking density on the chemical composition, the calorifi c value, the content of cholesterol and fatty acids profi le in tilapia (Oreochromis nilotius, Linneaus, 1875) were used 120 fi ngerlings with average initial weight of 4.0 g, distributed in 20 aquaria (70L) in a completely randomized design with 4 treatments, 50, 75, 100 and 125peixes/m 3 and 5 replicates. The ration supplied contained 36% crude protein and 3100kcal/ED/kg ration. At the end of cultivation, there was signifi cant difference (p<0.05) in the analysis of the fi nal weight and total weight gain between the different densities tested, the largest weight found for the density of 75peixes/m3. Regarding the analysis of body composition was observed difference ( <0.05) between the densities for the content of moisture, total lipids, crude protein, calorie and cholesterol. The polyunsaturated / saturated density was highest in the 100peixes/m 3 (11.76), since the density of 50peixes/m3 presented a sum of (6.85) for the content of EPA+DHA. In assessing the nutritional quality of lipids, the density showed the rates of n-6/n-3, hypocholesterolemic / hypercholesterolemic (HH) index of atherogenicity (IA) and index of thrombogenicity (IT) as favorable for consumption. It is concluded that the density of 50peixes/ m 3 may be a good source of fatty acids, particularly omega-3 acid and its value in HH.