Relationships between the addition rates of cellulase or glucose and silage fermentation at different temperatures

Abstract

The influence of the application rates of cellulase preparation and glucose on silage fermentation at different temperatures was studied with the straw of naked barley (Hordeum vulgare L. emand Lam) and guineagrass (Panicum maximum Jacq.). Addition rate of cellulase and glucose, temperature and their interaction had significant effects on pH value, lactic acid content, butyric acid content and propionic acid content of naked barley straw silage and significant effects on all the parameters of guineagrass silage (P < 0.01). Temperature and interaction had significant effect on acetic acid content (P < 0.05) and no significant effect on NH(3)-N content of naked barley straw silage (P > 0.05). Under all the temperatures, the pH values of barley straw and guineagrass silages were reduced by cellulase and glucose addition even at the lowest rate (P < 0.05), compared with their corresponding control. Lactic acid contents of silages were the highest within the same temperature and same additive when glucose and cellulase were added at the highest rates, whereas the effect of cellulase and glucose addition on butyric acid production varied with their application rates and silage storage temperature. The addition rate of restricting butyric acid fermentation was lower at 20 degrees C than that at 30 degrees C, and it was the lowest at 40 degrees C where cellulase and glucose addition restricted butyric acid fermentation even at 0.1 g/kg and 10 g/kg, respectively, when compared to the control. While the addition rate was lower than the above level, cellulase and glucose addition also promoted butyric acid fermentation.

The effects of wilting and storage temperatures on the fermentation quality and aerobic stability of stylo silage

“…However, when the wilting period was prolonged to 12 h in our research, the wilted stylo was significantly higher in NDF content and lower in WSC content than unwilted and 6 h wilted materials. In the LW and HW silages, butyric acid was not detected at either low temperature or high temperature, whereas the NW silage at 30°C contained higher butyric acid content than at other temperatures, which agreed about the result of Zhang et al (1997aZhang et al ( , 2010. In general, good silage depends on reasonable moisture contents of material.…”

“…On the other hand, Zhang et al (1997b) reported that storage temperature had no significant effect on pH, acetic acid and butyric acid contents of corn silage, while it had significant effect on all the fermentation parameters of guineagrass silage. Guineagrass silage kept at 30°C had less lactic acid and higher pH value than that kept at 40°C (Zhang et al 1997b(Zhang et al , 2010. Tjandraatmadja et al (1991) and Mitsuaki et al (1997) found lower butyric acid content or lower pH value at high temperature in their experiments.…”

Adding distiller's grains and molasses on fermentation quality of rice straw silages

“…Due to the low water soluble carbohydrates (WSC) content in straw, tremendous efforts have been made to improve fermentation quality and nutritive value of straw silage by supplying fermentation substrate directly or indirectly (LI et al, 2010, ZHANG et al, 2010. Molasses has been proven to be an effective silage additive by promoting lactic acid bacteria fermentation, reducing silage pH, discouraging clostridia fermentation and proteolysis, and generally decreasing organic matter losses when applied to crops with low water soluble carbohydrates (WSC) (BOLSEN et al, 1996).…”

The effects of agricultural byproducts on the fermentation quality of stylo silages

“…In addition, butyric acid was detected in BSLl added RG silage (2.7 g kg·1 DM), while it was not in other silages. The different results might be caused by different WSC contents and buffering capacity in various treatments [17].…”