Using a mechanistic model, we compared five alternative farming systems with the purpose of transforming monoculture (MON) banana farms into mixed farming systems (MFS) with ruminants feeding banana by-products (leaves, pseudostems and nonmarketable fruits) and forage from the fallow land. The paper presents the main structure of the model (land surface changes, available biomass for animals, stocking rates, productive or reproductive indicators), and impact assessment (change in farm productivity) is discussed. Five MFS with typical local ruminant production systems were used to compare MON to the strategies using forage from fallow and/or integrating Creole cattle (CC), Creole goats (CG) or Martinik sheep (MS) into banana farming. One hectare MON shifted into an MFS allows a stocking rate of 1,184, 285, and 418 kg of live weight per hectare for CC, CG and MS, respectively. Banana by-products seem to be better valorized by the CC scenario. However, parameters such as length of the cycle, local prices for cattle, goat and sheep meat, work time and farmer's skills in ruminant management may have been taken into account by the farmer when choosing the ruminant species to rear.