TEXTURE AND METABOLIZABLE ENERGY LEVELS OF THE DIET FOR BROILER CHICKENS FROM 1 TO 21 DAYS OF AGE. / FORMA FÍSICA E NÍVEIS DE ENERGIA METABOLIZÁVEL DA RAÇÃO PARA FRANGOS DE CORTE DE 1 A 21 DIAS DE IDADE.

ABSTRACT

This study aimed at evaluating the effects of feed form and diet metabolizable energy levels (ME) on broiler chickens performance from 1 to 21 days of age. Four hundred and eighty chickens were randomly assigned in a 2 x 3 factorial scheme ME (2900 and 3050 kcal/kg) and feed form (mash, crumbled, and extrused), with four replicates of 20 birds each. No interaction was observed between the factors on performance characteristics from 1 to 7 and 1 to 14 days. The studied factors did not influence chickens performance from 1 to 7 days. At 14 days, chickens fed extrused diets showed lower feed intake without impairing other characteristics. Also, broilers fed diets containing 3050 kcal/kg ME had better weight gain and feed conversion without influencing feed intake. A significant interaction between factors was found for weight gain and feed conversion from 1 to 21 days, where broilers fed crumbled diets with 2900 kcal/kg ME showed better performance. Feed intake was not influenced by ME in any age. It is possible to conclude that the use of crumbled diet allows a reduction in ME and promote better performance in relation to extrused and mash diet. Broilers chickens at initial phase do not control the feed intake according to ME of the diet at the studied levels. KEY-WORDS Crumbled diet. Extrused diet. Mash diet. Metabolizable energy. Pelleted diet. Performance.