A model of clostridial dominance in ensilage

A simulation model of the growth and fermentation of lactic acid bacteria and clostridia in silage is described. The model is used to predict the occurrence of a well-preserved lactate silage or a poorly-preserved clostridial silage. Results of the model are compared with published experimental studies not used in the model's development. The results are summarized with maps showing the combinations of initial water-soluble-carbohydrate content, crop buffering capacity, dry matter content, temperature, initial pH, and initial population of lactic acid bacteria which result in a clostridial silage. The specific processes modelled include the growth and death of lactic acid bacteria and clostridia; the use of substrate and accumulation of fermentation end products; release of ammonia; and change in silage pH.