Effect of Chemical Additives on Maize Silage Fermentation and Aerobic Stability and on Preference and Short‐Term Intake by Goats

ABSTRACT This study determined the effects of a mixture of sodium benzoate and potassium sorbate (SBPS; 2 L/t fresh matter (FM)) and a formic acid‐based mixture (FASF; 3 L/t FM) on maize silage fermentation, aerobic stability, and short‐term feed intake by goats. Whole‐crop maize harvested at 280 g/kg dry matter (DM) was untreated (CON) or treated with SBPS or FASF and ensiled in 120‐L plastic silos for up to 356 days. At opening, FASF had the highest DM losses (7.4%) and ethanol concentrations (36.6 g/kg DM), whereas CON had the highest and SBPS the lowest contents of ethyl lactate (399 vs. 199 mg/kg DM) and ethyl acetate (499 vs. 59 mg/kg DM). After silo opening, silages were exposed to air for 6 days. Aerobic stability was 34 h longer in SBPS (152 h) than FASF (118 h) and substantially longer than in CON (65 h). The onset of aerobic deterioration was earlier in CON, evidenced by a strong increase in silage temperature (> 30°C) and pH > 5. When the silages were exposed to air for 6 days, preference expressed as DM intake/3 h was lowest in CON (223 g), followed by FASF (423 g) and SBPS (692 g). The decline in CON was caused by deteriorating sensory properties. The application of the SBPS mixture to maize harvested at lower DM concentrations than usual (< 30%) prevented undesirable DM losses. The addition suppressed yeasts and degradation processes and improved aerobic stability for up to 6 days. The SBPS‐treated silages remained palatable even after aerobic exposure and were more preferred.