The body weight gain and linear increase of some morphometric traits in domestic ecotype chickens reared under traditional semi-intensive system for eight weeks were examined. A total of 146 chickens were selected from 10 farms across Ogbomoso and its environs. The birds were randomly assigned into two groups after taking their initial weights. Group A were maintained on full scavenging for food and water while group B were partly offered 50g maize pomace per bird daily in the morning before scavenging. Body weight increased exponentially in both groups, with more consistency in group B. Group B had higher AWG at third week of study. Correlation between body weight and the morphometric traits were higher in group B, ranging between 0.825 and 0.990. Supplementing feed of local ecotype birds reared under semi-intensive system with maize pomace improved weight and linear measurements, with shank length being more predictive of total body weight.