Hygienic profile and nutritive value of boot stage wheat silage treated with acid-based preservative
The current study was undertaken to investigate the effects of acid-based preservative (AP) on fermentation, hygienic and post-storage quality as well as digestibility of low dry matter (DM) direct cut wheat silages. Wheat was harvested at boot stage of maturity. Acid-based preservative was applied at 2 mL kg-1 (AP2), 3 mL kg-1 (AP3) and 4 mL kg-1 (AP4) of fresh forage weight. Silages with no additive served as control. After AP treatment, the chopped forages were ensiled in 1.5 L anaerobic jars. Four jars per treatment were sampled on d 90 after ensiling, for chemical and microbiological analysis. Overall, AP treatment did not affect the concentrations of lactic and acetic acid of the wheat silages. In contrast, inclusion of AP increased the concentrations of formic and propionic acid whereas decreased the concentrations of butyric acid, ethanol, ammonia-N and gas losses when compared to the control silage (P<0.05). Under aerobic conditions, AP treated silages had lower pH, CO2 production and the numbers of yeast and mold than the control silage (P<0.05). Fibrous fractions were decreased with the application of AP, but 96 h in vitro gas production and in vitro organic matter digestibility of the silages were not affected by AP inclusion. In conclusion, addition of AP onto direct cut low DM wheat has raised soluble sugars, reduced proteolysis and possessed antimicrobial properties and consequently improved fermentation and post storage quality.
acid preservative, boot stage, hygienic profile, nutritive value, wheat silage.