Studies on various factors affecting silage fermentation

I. Effects of soluble carbohydrate and protein on the quality of silage

Abstract

Effects of the amounts of soluble carbohydrate and crude protein of the ensiled grass and additives on the quality of the resultant silages were investigated in 4 experiments. Orchardgrass and green oats were ensiled in laboratory silos respectively with some carbohydrate materials and/or gluten. The measurement of pH and estimations of organic acids and volatile basic nitrogen were carried out after 70-day ensilage at room temperature.
The results obtained were as follows:
1. Increase in lactic acid production was the largest with glucose addition. Ground corn, corn starch, soluble starch and dextrin showed some effects, but the extent of lactic acid production by these materials were less than by corresponding amount of glucose. Molasses meal (a mixture of 42% molasses, ground corn cob, sufflower meal and cottenseed hull bran) had considerable effect of improving silage quality.
2. In one experiment, in which the control silage showed poor quality with much butyric acid and high pH, increasing protein content in the ensiled material by the addition of gluten resulted in poor silages containig much butyric acid. This adverse effect was proportional to the amount of added gluten at each level of soluble carbohydrate content.
However, in the other two experiments, in which the control silage contained no butyric acid, the addition of gluten did not show any adverse effect on the quality of the resultant silage.
3. When the grasses of high soluble carbohydrate content was ensiled, silages of good quality were always obtained without any additive. There was, however, one case where good silage was obtained in spite of the extremely low levels in both soluble carbohydrate content and the ratio of soluble carbohydrate to crude protein in the grass.