An experiment was carried out to evaluate the effect increasing levels of yeast wall and broiler breeders' age levels on lymphoid organs weight, cellular immune response and hematological parameters in broilers. A total of 3,360 Cobb broilers were allotted, in a completely randomized design and a 2x5 factorial arrangement, and two controls, compound of two broiler breeders age (34 and 57 weeks of age) and five yeast wall levels (zero, one, two, three and four kg of yeast wall/ton of diet). Broiler breeders' age affected all studied variables. The inclusion of 3kg of yeast wall/ton of meal increased, at 57 weeks age broiler breeders, more intense inflammatory reaction when compared to control diet; however the circulated heterophils and lymphocytes numbers were not increased. In conclusion, the use of yeast wall, associated or not to sorghum on broilers diet still needs complementary studies, for example, purified components of yeast wall (MOS and ß-glucano).
Hematology; immune response; sorghum; yeast wall
