The Effect of Chemical Additives with Anti-Fungal Properties on the Fermentation and Aerobic Stability of Corn Silage
The objective of this study was to evaluate chemical additives with antifungal properties on the fermentation and aerobic stability of corn silage harvested at two maturities: 32% DM (LDM) and 38% (HDM) whole-plant DM. At each harvest, plants were obtained from five random locations within the field and further divided into four piles and treated with a) no additive, b) 1.5 L of Safesil (Salinity Agro, Halmstad, Sweden; active ingredients of sodium nitrite, potassium sorbate, and sodium benzoate)/t of fresh forage, c) 2 L of Safesil/t, or d) 2 L of Crop Saver (CS, CNH America LLC, Racine, WI; 64.5% propionic acid). Each pile was treated with a total volume of 0.03% vol/wt of liquid (water alone for the no additive treatments). Forage from each pile was ensiled in 7.5-L lab silos (packing density of about 220 kg of DM/m3). Silage data were analyzed as a 2 (maturity) × 4 (additive) factorial arrangement of treatments after 120 d of storage (22 ± 2°C) using the software JMP. At both harvest DM, compared to untreated silage, treated silages had similar (P > 0.05) concentrations of lactic and acetic acids, CP, ADF, NDF, starch and pH. Treatment with CS increased (P < 0.01) the concentrations of propionic acid silage in silage in both maturities compared to other treatments. In LDM silages, treatment with Safesil did not affect (P > 0.05) the concentrations of ethanol but treatment with CS resulted in a higher (P < 0.01) concentration of ethanol when compared to untreated silage. In HDM silage, concentrations of ethanol were lower (P < 0.01) in a dose dependent manner for silages treated with Safesil but unaffected by CS. Compared to untreated silage, aerobic stability was improved (P < 0.01) for both maturities treated with CS (66 vs. 93 h in LDM silage and 59 vs. 116 h for HDM silages). Treatment with Safesil was even more effective resulting in aerobic stabilities (P < 0.01; average of > 450 h in LDM silages and average of > 350 h in HDM silages) that were markedly better than both untreated and CS. This study was the first to show that Safesil has the potential to markedly improve the aerobic stability of corn silage in North America.
silage, aerobic stability, corn silage