Proximate analysis of maize cobs (MC) was carried out with samples from two different sites. The average values of CP, CF, NFE, EE, Ash, Ca and P were 2.47, 32.22, 57.73, 1.66, 5.16, 0.15 and 0.075 percent respectively. The apparent metabolizable energy of MC was found to be 751.68 Kcal/kg. Two experiments were also conducted to evaluate the replacement value of MC for maize in egg-type chick and grower rations. In experiment I, three hundred and fifteen day-old chicks were used. Seven isonitrogenous (20% CP) chick diets were formulated to contain graded levels of ground MC at 0, 5, 10, 15, 20, 25 and 30 percent of the diets. This feeding trial lasted from one day-old up to seven weeks of age. For experiment two, there were two phases. The growing and the early laying phases. In the growing phase, seven 15% CP diets containing ground MC at 0. 10, 20, 30, 40, 50 and 60% levels were fed to two hundred and seventy three 8-weeks old pullets. At the end of the first phase which lasted for 12 weeks, two birds from each replicate group were sacrificed and length of the intestines and caeca were measured. A section of the duodenum was also taken and villi abrasion was assessed under photomicroscope. In the second phase, two hundred and ten pullets from phase 1 were transfered in their original groups to the laying house. A common layer ration of 17% CP was offered to all the groups for four 28-day periods. Results from the chick study indicate that the final body weight, weight gain and feed-gain ratio for the control group were significantly (P<0.05) superior to those of other groups that were fed various levels of MC. Feed consumption increased significantly (P<0.05) with increase in the dietary level of MC as from 15% level. Feed cost per bird decreased with increase in the dietary level of MC above 10% and mortality was not affected. Results for the growing phase showed satisfactory body weight gain and feed-gain ratio of pullets fed up to 20% dietary level of MC. Feed consumption increased significantly (P<0.05) with increase in dietary level of MC. The MC diets also increased significantly (P<0.05) the length of intestines and caeca as well as the abrasion of the Villi. During the laying phase, pullets fed high levels of MC grower diets exhibited compensatory growth and attained similar body weights with those that were fed on control and lower dietary MC. Percent hen-housed egg production was satisfactory with the 10% and 20% MC diets when compared with the control group and the percent hen-day egg production was not affected up to 30% dietary MC treatment. Based on these observations, it was recommended that MC should not be used in chick ration formulations while the grower diets may contain up to 20 percent of this agricultural by-product with no adverse effects on the performance of the birds. At 20% level of inclusion, MC replaced 31.05% of the dietary maize and reduced feed cost by about 8%.