Ruminal kinetics of carbohydrates, gas production and bromatology of sugarcane silage with high levels of sodium benzoate

The objective of this study was to evaluate the chemical composition, ruminal kinetics, gas production and aerobic stability of sugarcane silage added with increasing levels of sodium benzoate up to 1% of the natural matter. After harvesting, the sugarcane was chopped and placed in experimental polyethylene silos for storage for 30 days. An increasing concentration of sodium benzoate in the silage promoted a linear decrease in the crude protein content, varying from 2.79% to 2.51%. The addition of sodium benzoate reduced the fiber concentration of the silage (P = 0.0015) and increased gas production of the fibrous and nonfibrous carbohydrates (R2 = 0.83 and 0.65, respectively). The volume and rate of degradation of nonfibrous carbohydrates (Vcnf and Kdcnf, respectively) were significantly affected (P < 0.05) by the inclusion of sodium benzoate, with the largest volume of gas produced by fermentation of nonfibrous carbohydrates with a dose 0.25% of sodium benzoate and, not coincidentally, it was the treatment that presented the lowest Kd (5.52 g DM-1). The aerobic stability was higher in the silage with the highest additive content than in the other silages. The high levels of sodium benzoate used in this work, above what is commonly studied, have been shown to improve sugarcane silage with dry matter contents that are normally difficult to control.