Valina digestível para frangos de corte em região de clima quente

Abstract

In order to evaluate the demands of digestible valine in male broiler chickens raised under hot weather, there were conducted three experiments in the experimental farm of the University of Mato Grosso with the objective of evaluating the necessity of the digestible valine for broiler chickens raised under a hot weather condition. In the experimental farm in the Federal University of Mato Grosso. In these experiments, there were used 864 chicks Coob 500 in the early stage of life (8 to 21 days), 720 chicks in stage of early growing (22 to 33 days) and 720 chicks in the final stage (34 to 42 days). The trial design used was entirely randomized with six treatments with eight repetitions. The treatment used six levels of digestible valine (7,87; 8,37; 8,87; 9,37; 9,87 e 10,37g for kilogram of ration) in the initial phase, days it was used levels of 7,32; 7,82; 8,32; 8,82; 9,32 e 9,82 grams de digestible valine per kilo of ration, during the growing phase and it was used the levels of 6,77; 7,27; 7,77; 8,27; 8,77 e 9,27 grams of digestible valine per kilo of ration during the final phase. According to the obtained results, during the initial phase it was observed a increasing linear growing ratio for the consumption of ration as the level of valine increased in the diet and a quadratic increase in weight gain. In the chemical composition of the 21 days there were an effect of decreasing linear effect for the percentage of dry matter in the carcass and in the feathers and an effect of linear increasing for the percentage of raw protein in the carcass. In the growing phase there were a quadratic effect for the consumption of ration, weight gain and food conversion. For carcass return and cuts in the 33 days there were a quadratic effect for relative weight of the gizzard and length of the small intestine. In the chemical composition there was a increasing linear effect for the percentage of mineral matter, protein and ether extract in the carcass. In the final phase the performance was not affected by the treatments. For the carcass and cuts return in the 42 days there was a quadratic effect only in the relative weight of the liver. In the chemical composition there was a decreasing linear effect only for the mineral matter in the carcass. It is recommended for male broiler chickens, raised in regions of hot weather the levels of 7,87g; 8,74 e 6,77g/kg of digestible valine during the phase of 8 to 21 days, 22 to 33 days and 34 to 42 days, respectively.