Brito et al., 2011. Rev. Bras. Zootec., 40 (10): 2147-2151

This experiment was carried out to evaluate the digestibility of the amino acids from corn, soybean meal and corn germ meal in cecectomized roosters and broilers. The experiment used sixteen Lohmann-LSL roosters with 45 weeks of age, 20 AgRoss 508 male broilers with 21 days of age and 20 other male broilers of same line, with 42 days of age, all of them cecectomized. A completely randomized arrangement with three animal categories (roosters; chickens at 21 and 42 days of age) was adopted for each feedstuff analyzed. Each bird represented an experimental unit. The trial had a duration of 84 hours; in the first 36 hours roosters and chickens were submitted to fasting for intestinal cleaning. After this, birds were forced to ingest 30 grams of each ingredient with an esophageal probe, introduced directly into the crop. During the subsequent 48 hours, the excreta produced was collected twice a day. The values for true digestible amino acids were reduced for corn and full-fat corn germ meal when determined with broilers submitted to the experimental procedures at 21 days of age compared to the control group (adult cockerels). But, the same results were not been observed for soybean meal. In general, the true digestible amino acid values were higher when determined with broilers at 42 days of age compared to adult cockerels. The total amount of true digestible amino acids determined were 7.24; 6.25 and 7.33% for corn, 9.66; 9.14 and 9.91% for corn germ meal and 41.82; 41.78 and 42.02% for soybean meal, values determined with roosters, and broilers at 21 and 42 days of age, respectively. It was observed that as the gastrointestinal tract is mature, the amino acid digestibility of birds that consumed corn and corn germ meal is enhanced.