Silage microbiology and its control through additives

TLDR

Ensiling preserves moist crops by creating an anaerobic, low‑pH environment that suppresses spoilage microbes through lactic acid fermentation, and inoculants are now the primary additives used to enhance this process. The authors use inoculants containing Lactobacillus buchneri, a heterofermentative bacterium that converts lactic acid to acetic acid during ensiling. Homofermentative strains accelerate anaerobic suppression, boost dry‑matter recovery and animal performance, while the acetic acid produced by L.

Abstract

Ensiling is a method of preserving a moist crop. A moist crop can support the growth of a wide range of microorganisms, most of which will degrade the nutrient value to livestock. However, ensiling generally controls microbial activity by a combination of an anaerobic environment and a natural fermentation of sugars by lactic acid bacteria on the crop. This fermentation and the resulting low pH primarily suppress the growth of other anaerobic microorganisms. The fermentation can also inhibit yeasts, molds and aerobic bacteria, but the anaerobic environment is essential to preventing most of the spoilage microorganisms from growing. Inoculants have become the dominant additives for making silage. Homofermentative strains help guarantee a rapid suppression of anaerobic stains early in storage, increase dry matter recovery and have improved animal performance by means that we do not fully understand. Inoculants containing Lactobacillus buchneri, a heterofermentative species capable of fermenting lactic acid to acetic, are recent additives. The added acetic acid inhibits yeast and mold growth, increasing aerobic stability of silages at feeding.