Effect of inoculants of different composition on the quality of rye silages harvested at different stages of maturity

Abstract

Winter rye (Secale cereale L.), one of the small-grain winter annuals, can be used as a cover crop for protection against soil erosion for absorption of unused soil nitrogen, and for cattle feed by preserving as silage. The experiment was conducted with the objective to evaluate the potential of the blend of homofermentative and hetero- and homofermentative lactic acid bacteria (LAB) as a rye silage additive. Early-cut rye (at boot stage, wilted) and whole-crop rye (at milk and soft dough stages of grain) were ensiled in laboratory mini-silos with (1) a blend of homofermentative LAB strains containing Lactobacillus plantarum (DSM26571), Enterococcus faecium (DSM22502), and Lactococcus lactis (NCIMB30117), (2) a blend of hetero- and homofermentative LAB strains containing Lactobacillus plantarum (DSM26571), Enterococcus faecium (DSM22502), and Lactobacillus buchneri (DSM22501), or (3) a blend of hetero- and homofermentative LAB strains containing Lactobacillus buchneri (DSM22501) and Lactococcus lactis (DSM11037). They were compared to ensiling without additive. After 60 days of fermentation at room temperature, mini-silos were opened, sampled for proximate analysis, forage hygiene, fermentation profile, and subjected to an aerobic stability (AS) test. Although the addition of homofermentative LAB strains was effective in reducing fermentation losses, it impaired the aerobic stability of rye silages. The combination of hetero- and homofermentative LAB strains was effective in reducing the aerobic deterioration of the rye silages by supporting a low pH value and inhibiting the proliferation of yeast and moulds.