Aerobic Deterioration of Wheat, Lucerne and Maize Silages Prepared withLactobacillus acidophilusand aCandidaspp.

摘要

Aerobic deterioration of lucerne, maize and wheat silages was characterized by rapid increases in yeast and mould flora which oxidized lactic and volatile acids resulting in increased temperature and pH. While populations of yeasts and moulds were similar, temperature increases were slightly greater for silages inoculated withLactobacillus acidophilusandCandidaspp. After 48 h the pH of the inoculated silages was higher in general and concentrations of acids were lower than controls. Bacterial growth was slight although continued lactic acid production was probable. In contrast to lucerne and maize silages, the pH of wheat silage remained stable during this period because of high butyric levels, but temperature and yeast populations increased. After 48 h the pH rose above 5 in maize and lucerne, and bacterial growth and metabolic activity resumed resulting in volatile and non‐volatile acid production from carbohydrate fermentation and deamination of amino acids. During this phase of aerobic deterioration yeast growth slowed or stopped, but temperatures remained high and pH continued to climb probably because of production of ammonia. The changes in gross composition of the silages did not follow any particular pattern. Losses in dry matter were small (2.5–4.0) and changes in individual components probably reflect this loss rather than substantial changes. Protein availability in the lucerne silages undoubtedly decreased, as protein losses were high. It is concluded that the aerobic deterioration of silage is enhanced by the addition ofL. acidophilusandCandidaspp. at ensil