An experiment was conducted to examine effects of five levels of dietary protein (25, 27, 29, 31 y 33%) on performance by the gamitana, Colossoma macropomum Cuvier 1818. The parameters measured were weight gain (WG), food conversion (Fe), retained protein (RP), protein efficiency ratio (PER), and retained energy (RE). To prepare the experimental diets were used as protein sources anchovy meal and soybean meal, and as energy sources yellow corn, wheat bran and oil fish. Were found significant differences (P

The sparing effect of the dietary protein using diets with high energy levels was evaluated. A factorial design was used to examine the interaction of two levels of protein (30 and 35%) and two levels of digestible energy (3.3 and 3.7 kcal/g) on the weight gain (WG), food conversion FC), retained protein (PR), retained energy (ER) and protein efficiency ratio (PER) in “sex reversal Nile tilapia” (Oreochromis niloticus). Diets contained anchovy and soybean meal as protein sources and yellow corn and wheat bran as energy sources. The fish oil was used to adjust the energy levels. There were highly significant interactions (P<0.01) between the experimental diets. In diets with 30% proteins, the increase of digestible energy significantly enhances WG, FC, PR, ER and PER, where the level of 3.7 kcal/g had the best performance. With 35% protein, the increase of digestible energy had not...

Un experimento fue conducido para evaluar los efectos de cinco niveles de proteína (25,27, 29, 31 y 33%) sobre el comportamiento productivo de alevinos de la gamitana, Colossoma macropomum Cuvier 1818, alimentados con dietas isocalóricas (2,7 kcal de ED/g). Los parámetros medidos fueron ganancia de peso (GP), conversión alimenticia (CA), proteína retenida (PR), razón de eficiencia proteica (REP) y energía retenida (ER). En la preparación de las dietas experimentales se utilizaron como fuentes de proteína harina de anchoveta y harina de torta de soya y como fuentes de energía maíz amarillo duro, subproducto de trigo y aceite de pescado. Se encontraron diferencias significativas (P<0,05) entre tratamientos para los parámetros GP, PR, REP y ER. No se encontraron diferencias significativas para la CA. Los mejores rendimientos fueron obtenidos cuando las gamitanas fueron alimen...

The sparing effect of the dietary protein using diets with high energy levels was evaluated. A factorial design was used to examine the interaction of two levels of protein (30 and 35%) and two levels of digestible energy (3.3 and 3.7 kcal/g) on the weight gain (WG), food conversion FC), retained protein (PR), retained energy (ER) and protein efficiency ratio (PER) in “sex reversal Nile tilapia” (Oreochromis niloticus). Diets contained anchovy and soybean meal as protein sources and yellow corn and wheat bran as energy sources. The fish oil was used to adjust the energy levels. There were highly significant interactions (P<0.01) between the experimental diets. In diets with 30% proteins, the increase of digestible energy significantly enhances WG, FC, PR, ER and PER, where the level of 3.7 kcal/g had the best performance. With 35% protein, the increase of digestible energy had not...