Calving interval, age at first calf and calf mortality rates are related to the condition of cows, based on the survey data of Wirdahayati (1994) and field observations. The derived functions indicate that a 200 kg animal will have its first calf at around 30–36 months of age, and a cow needs to be approximately 260 kg to have a calf at 12-monthly intervals. Labour requirements for cut and carry of necessary forage are varied according to forage availability. The greater the shortage of forage, the greater the labour requirement as smallholders need to collect forage from greater distances or spend time herding animals on common land.