A Bali cattle production model was developed that combines published secondary data and field data from project activities relating to animal liveweight, liveweight gain, milk production, age at first calf and calving interval, as well as the quality, composition and quantity of the various sources of feed. The model is principally based on the energy functions outlined by SCA (1990) with coefficients recalibrated for Bali cattle, but includes intake restrictions based on estimated crude protein requirements of Bali cattle (Poppi et al., 1999).