The aim of this study was to assess the performance of lactating dual purpose cows (milk and calves), supplemented with 2 sources of energy: molasses (Mo) or ground corn (Gc) during the dry season under subtropical conditions in Mexico. In the subtropical regions of Mexico, during the dry season there is a lack of quality and quantity of fodders to support lactating cows and their suckling calves under grazing systems. Therefore, farmers supplement their cows to maintain milk production and calves weight gain. Supplements are based on cracked corn, cob and husk (CCH), soybean meal and urea (70 g/cow/d). The CCH processing method reduced ruminal starch digestibility, limiting the potential energy cows could obtained from the supplement. Treatments (TX) consisted of molasses or ground corn at 6% inclusion in CCH supplement (5 kg of DM cow/d). Response variables were recorded every 2 weeks, considered as experimental periods (EP). Milk, milk components, body weight, calves weight and body condition score, were subjected to a mixed model procedure from SAS 9.0 for a complete randomize experimental design. Cow was defined as a random effect. There were no significant differences among response variables due to TX (milk yield 7.1 vs 7.0 kg/cow/d, molasses and ground corn TX, respectively), but there were differences (P < 0.05) for EP on milk yields which increased by the end of the experiment with milk yields of 6.5 and 8.6 (kg/cow/d, EP 1 and 5, respectively). There were no differences on animal response variables when molasses or ground corn at 6% inclusion were added to supplements as an extra source of energy.