This study examines the potential of quality protein maize (QPM) as an animal feed ingredient in Brazil and EI Salvador. The minimum ingredient cost of pig and chicken feed with and without QPM and the optimal level of the main ingredients in the rations are obtained using linear programming models and compared for both cases. Sensitivity analysis is performed on relative prices of soybean meal (the main protein source), regular maize and sorghum (the main energy sources), synthetic lysine (the main amino acid supplement), and QPM. Model results indicate that QPM has the potential to reduce the production cost of pig feed by as much as 5.0% in Brazil and 3.4% in EI Salvador. Chicken feed cost savings of QPM are as high as 2.9% in Brazil and 2.8% in EI Salvador. If assigned the same price as regular maize, QPM constitutes 80% of the optimal pig feed in Brazil, replacing all regular maize and synthetic lysine and 40% of the soybean meal. At a 5% price premium over regular maize, QPM constitutes 50% of the optimal pig diet. In EI Salvador, QPM priced the same as regular maize also forms 80% of the pig diet; at a 5% price premium, QPM constitutes 40% of the diet. In both countries savings at the industry level depend on the size and technological sophistication of the pig industry and on the prices of the feed ingredients with which QPM competes. Future research and agricultural policy should emphasize means of distinguishing QPM from regular maize, improvement of QPM's storability, and promotion of QPM varieties already available.vii, 45 pages