Exigência de lisina, arginina, valina e isoleucina digestível para codornas de corte

Abstract

Four experiments were carried out in order to estimate the requirements of digestible lysine, arginine, valine and isoleucine for growing meat quails (Coturnix coturnix sp). In experiment 1, in order to determine the digestible lysine (DL) and digestible arginine (DA) requirements in the period of 1 to 14 days old, were used 2160 meat quails with a day old, not sexed, in a completely randomized design with a 4x4 factorial arrangement, with four levels of DL (1.10, 1.40, 1.70 and 2.00%) and four levels of DA (1.22, 1.52, 1.82 and 2.12%), totaling 16 treatments with three replications and 45 quails per experimental unit. The body weight (BW), weight gain (WG) and cumulative biomass body (CBB) were affected in a quadratic way, estimating 1.57% of DL and 1.67% of DA in ration. In experiment 2, in order to determine the requirement for DL and DA in the period of 15 to 35 days old were used 1440 meat quails, not sexed, distributed in a completely randomized design with a 4x4 factorial arrangement, with four levels of DL (0.90, 1.20, 1.50 and 1.80%) and four levels of DA (1.00, 1.30, 1.60 and 1.90%) totaling 16 treatments with three replications and 30 quails per experimental unit. In the period from 15 to 28 days, the WG, CBB and feed conversion (FC) were affected in a quadratic way as a function of increasing levels of DL and DA in experimental diets with estimation of maximum gain at 1.59% of DL and 1.61% of DA. In experiment 3, in order to determine the digestible valine (DV) and isoleucine (DI) requirement in the period of 1 to 14 days, were used 2160 meat quails with a day old, not sexed, distributed in a completely randomized design with a 4x4 factorial arrangement, with four levels of DV (0.90, 1.10, 1.30 and 1.50%) and four levels of DI (0.80, 1.00, 1.20 and 1.40 %), totaling 16 treatments with three replications and 45 quails per experimental unit. The BW, the WG and the CBB linearly increased in function of DV levels and were influenced in a quadratic way estimating 1.38% of DI. It was concluded that the requirements of DV and DI for maximum performance of meat quail from one to 14 days of age were 1.50% and 1.38%, respectively, corresponding to relations: valine: lysine of 95% and isoleucine: lysine of 88%. In Experiment 4, in order to determine the requirement of DV and ID in the period of 15 to 35 days, were used 1440 meat quails, not sexed, distributed in a completely randomized design with a 4x4 factorial arrangement, with four levels of DV (0.82, 1.02, 1.22 and 1.42%) and four levels of DI (0.73, 0.93, 1.13 and 1.33%), totaling 16 treatments with three replications and 30 quails per experimental unit. The performance of meat quails from 15 to 35 days of age was not affected by increased levels of DV and DI in the experimental diets, indicating that the lower levels evaluated, 0.82% DV and 0.73% of DI, corresponding to relations valine: lysine of 52% and isoleucine: lysine of 46% were sufficient to meet the nutritional requirements of meat quails without compromising performance.