Abstract
Three experiments were made to determine whether formic acid treatment or mixture of bacterial inoculant and enzyme treatment would improve the fermentation properties of unwilted orchardgrass and timothy silages, and unwilted and wilted alfalfa silages. In all experiments, the untreated silages made without additive were badly preserved. In experiments 1 and 2, the formation of butyric acid and volatile basic nitrogen (VBN) were slight in formic acid-treated timothy silage. The formic acid-treated orchardgrass silage was poorly preserved. The pH value of this silage rose to 5.64, accompanying high butyric acid and VBN concentrations. The addition of inoculant and enzyme led to well preserved silages in orchardgrass and timothy. The formic acid-treated timothy silage contained high residual water-soluble carbohydrate (WSC). In experiment 3, all the formic acid-treated alfalfa silages were well preserved except a wilted silage from the second cut. The inoculant and enzyme treatment was effective in improving the silage quality for first cut unwilted alfalfa but was not for other alfalfa materials. The residual crude protein and WSC contents of all the formic acid-treated alfalfa silages were higher than those of the other alfalfa silages. The results of this study indicate that the effectiveness of the formic acid- treatment on the silage quality depends on the herbage materials used and the treatment with the mixture of bacterial inoculant and enzyme is insufficient to produce a satisfactory fermentation in alfalfa silage.
