Níveis de energia digestível sobre os desempenhos reprodutivo e zootécnico e a deposição de lipídios nos hepatócitos de machos de tilápia-do-nilo

This experiment was carried out to evaluate the reproductive and zootechnical performance, and lipid deposition in the liver tissue of the Nile tilapia males fed diets containing different levels of digestible energy obtained from inclusion of soybean oil. Four hundred 400 broodfish (300 females and 100 males) were assigned to a completely randomized design composed of five levels of digestible energy (2,700, 2,950, 3,200, 3,450 and 3,700 kcal digestible energy.kg of feed-1) and four replications. The breeding were fed diets containing 35% of crude protein and submitted to hapas reproductive management for 101 days. The model adjusted by multiple regression analysis suggests the best result for sperm concentration and percentage of normal sperm for breeding fed diets containing 3.465.56 and 3.443.43 kcal digetible energy.kg of feed-1, producing 7.98 × 109 sperm.mL of semen-1 and 38.98% of normal sperm, respectively. The diet energy levels also caused an increase of lipid inclusion in the hepatocytes. The sperm production, seminal pH, sperm survival index and sperm activation time were not affected by energetic levels of the diets. The zootechnical performance was not affected by the energy levels of the diets either. The energy levels in the diets caused a linear increase in the lipid inclusion in the hepatocytes and affected the sperm quality by stimulating the spermatozoa production and the improving of normality indices of sperm morphology in energy levels around 3,450 kcal digestible energy.kg of feed-1.