Since 2004, a large range of forage species tolerant to drought, aluminium saturation and soil acidity, have been used to regenerate savannah grasslands and to diversify farming production. Specific trials have been carried-out to evaluate adaptability and the seed production of various forage species. The present study seeks to evaluate the agronomic and economic components of cattle fattening using improved forage species (Brachiaria ruziziensis) and thermophosphate inputs.