A study was conducted to investigate the bio-economics of feeding broiler chickens graded levels of cassava root meal based diets, as replacement for maize at 0, 25, 50, 75 and 100% to form treatment diets T1 , T2 , T3 , T4 and T5 respectively, with adjustment in soybean levels across the treatment diets to have iso-nitrogenous diets. Two hundred and forty- 4 weeks old 'Amos' strain broiler chicks were in a completely randomized design allotted randomly to five treatment groups of 48 birds each and of three replicates with each replicate having 16 birds. Parameters measured included weight gain, feed intake, feed gain ratio, price per kg of feed, price per kg of broiler and weight of carcass cuts. Data were analyzed using analysis of variances. Daily weight gain for T 1, T2 , T3 , T4 and T5 were 41.16g/b/d, 39.43, 33.47, 25.25 and 16.91 g/b/d, respectively while, daily feed intake for T1 , T2 , T3 , T4 and T5 were 113.35g, 112.75, 102.31, 93.34 and 85.94g, respectively. Results showed weight gain feed intake and feed Conversion ratio values to be significantly (P<0.05) depressed as the level of replacement of maize with cassava root meal exceeded 25%. Among the carcass parameters, only the dressed carcass (%) and thigh (%) weight values showed significant (P<0.05) decrease as the level of replacement level of maize with cassava root meal exceeded 25% while, spleen (%) and liver (%) values showed progressive increase (P<0.05) in weight as the level ofcassava root meal increased in the diets. Cost of feed decreased (p<0.05) significantly with the increasing level of cassava root meal. However, it did not translate to increase in price per kg of bird. It could therefore be suggested that cassava root meal should not exceed 25% as replacement for maize in broiler finisher diets, as beyond this level growth performance is adversely impaired.
Keywords: cassava root meal, bio-economics, growth performance, iso-nitrogenous, broiler chicke