Abstract
The aim of this study was to evaluate the effectiveness of β-glucans and MOS, essential oil (mixture of carvacrol and thymol), and the probiotic based on Saccharomyces boulardi, as an alternative to anticoccidial agents. In this experiment, six hundred seventy-two 1-day-old male broiler chicks were housed in batteries for 28 d. The experimental design of 4 randomized blocks with 24 cages each, and 7 birds per cage, consisted of an initial phase from 1 to 14 d of age, and a growth phase, from 15 to 28 d of age. The rations were formulated based on corn and soybean meal as energy and protein ingredients, respectively. All birds were inoculated with Eimeria spp and C. Perfringes at 14 d of age, and with C. Perfringes only at 21 d of age. The results showed the best weight gain in the initial phase when the anticoccidial agent was applied, whereas the use of additives in growth and entire experimental phases showed superior results in all treatments for this parameter. The birds that did not receive additives in the rations had the worst feed conversion in both phases and along raising. The results showed no significant differences between the treatments for the scores of lesions in the digestive tract and counts in the cecum, however, the red lesions increased numerically in the duodenum and jejunum of birds fed diets without the inclusion of additives. The use of additives indicated effectiveness for the parameters of performance in broilers challenged with C. Perfringes and Eimeria spp. at 14 d of age, and with C. Perfringes at 21 d of age.