Whole-crop cereal silages, such as wheat, sorghum, and maize are susceptible to aerobic deterioration, especially in warm climates. This is because aerobic yeasts are the most active at 20-30°C (Ashbell et al., 2002). Therefore, it is very important to find suitable additives that inhibit fungi and protect the silage upon aerobic exposure. Propionibacterium acidipropionici is propionic acid bacteria (PAB), which produce propionic and acetic acid in silage. Results with these micro-organisms in laboratory studies were promising with regard to aerobic stability. The purpose of the present work was to study the effects of PAB, lactic acid bacteria (LAB) and combinations of PAB + LAB on the fermentation and aerobic stability of whole-crop cereal silages