A Meta-Analysis of the Effects of a Chemical Additive on the Fermentation and Aerobic Stability of Whole-Plant Maize Silage

Our objective was to conduct a meta-analysis on the effects of a chemical additive containing sodium benzoate, potassium sorbate, and sodium nitrite on the fermentation and aerobic stability of whole-plant maize silage. We used data from 28 experiments, with 56 untreated to treated comparisons, carried out over a 9-year period. The influence of dry matter (DM) content and length of ensiling on the additive effect were assessed by meta-regression and subgroup analysis. Treatment with the additive reduced the pH and concentrations of ammonia-N, lactic acid, and ethanol, but increased the concentration of residual reducing sugars, DM recovery, and aerobic stability (by about 5 days). As the forage DM decreased, there was a greater reduction in ethanol by the additive treatment. The additive reduced the number of yeasts in silages made with forage harvested at >32% DM. The improvement in aerobic stability by the additive increased as ensiling time progressed. Overall, these findings show that the chemical additive has the ability to consistently and markedly improve the aerobic stability of maize silage under a wide range of conditions.