'Editora da Universidade Federal Rural do Semi-Arido - EdUFERSA'
Abstract
This work objectived to evaluate the influence of the calcium levels reduction (0.75 and 0.60%), using two suplemental sources in the diet, limestones of two distinct deposits of calcareous rock (A and B), for female and male broiler chickens in the period between 1 to 28 days of age, and thus, its effect on the performance and the bone development. For such purpose, had been used 288 female and 288 male cobb line broilers, by entirely randomized design in factorial arrangement (2x2x2). The food intake and live weight gain had presented significant differences
for the calcium sources, while the calcium level and the sex of the chickens had influenced the feed conversion, the mineralization and the length of the tibia bone. The reduction in the calcium level to 0.75% with the tested limestones, in males and females, provided to satisfactory performance, bone mineralization and calcium retention