Machado et al., 2007. Rev. Bras. Zoot., 36 (4, Supplement): 1113-1118

This study was conducted to determine the effect of spent mushroom substrate (SMS) ( Agaricus blazei) on the performance of broiler chicks at 1-42 days old. Six diets with 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0% SMS and one diet with 10 ppm avilamycin (antibiotic) were given to the birds. 588 chicks, 1-day-old, were allotted to a completely randomized design with six replicates per diet (three per sex) and 14 birds per experimental unit. It was observed that the birds fed with any level of SMS had the lowest performance, >0.4% SMS caused a gradual reduction in broiler performance. The 0.2% SMS provided the highest liveweight gain to the chicks, while 0.21% SMS gave the highest feed conversion and feed intake. The SMS had no effect on carcass and cut yields, except for chest and abdominal fat yield. It is suggested that mushroom substrate of Agaricus blazei can be used as an alternative to antibiotics at the level of 0.2% in the diet of broilers without affecting the performance and carcass yields.