Two trials were carried out to estimate the nutritional requirement and carcass composition of male broiler breeders according to five levels of metabolizable energy (ME) ingestion. Four hundred and fifty females and 75 males of Cobb-500 strain were selected to evaluate body weight, semen volume, spermatic concentration, motility, vigor and fertility of spermatozoa. Thirty males were used for evaluation of carcass chemical composition (DM, CP and crude fat [CF]) as a function of energy intake. The experiment was analyzed as a completely randomized design with five treatments (290, 310, 330, 350 and 370 kcal of ME/rooster/day). In the first trial (reproductive performance), each treatment was represented by 15 replicates of one rooster and six females. In the second trial (carcass evaluation), each treatment consisted of two replicates of three roosters (three slaughtered at 45 weeks and three at 61 weeks of age). Treatment quadract effect on motility, vigor and the fertility of spermatozoa was observed. Body weight and contents of fat and CP in the carcass increased linearly as ME intake increased. Based on the estimates of mobility, vigor and fertility, the 347 kcal of ME/rooter/day level is recommended to meet the requirements of male broiler breeders from 26 to 61 weeks of age.
fertility; nutrition; performance reproductive; semen
