high moisture corn, winter cereals, microbial additives, chemical additives, aerobic stability
Abstract
Microbial inoculants have been used as a tool to improve the fermentation and aerobic stability (AS) of high moisture grain silages. To access the effects of additives in high moisture corn silages (HMCS), thirty-five scientific papers were reviewed. Other six scientific papers were used to investigate changes in winter cereal grain silages (HMWCS). Application of chemical additives in HMCS preserved WSC due to inhibition of fermentation. Yeast growth was efficiently controlled, reducing ethanol production and linearly increasing AS. The HMWCS treated with chemicals showed a marked reduction in fungal growth and in ethanol formation, and a higher AS. The inoculation of HMCS with homolactic bacteria decreased silage pH by 0.26 unit and decreased proteolysis, but did not promote AS. The HMCS inoculated with heterofermentative strains had lower WSC and higher content of weak acids with antifungal properties, reducing mold and yeast counts and increasing AS. Maximum improvement in AS was achieved when heterofermentative bacteria were applied at 4.67 × 105 cfu.g-1 (P < 0.01, R2 = 0.50). The combination of homo and heterofermentative bacteria in HMCS ensured a lower pH and decreased yeast counts and ethanol production, whereas AS was not changed. Since fermentative losses were usually low, we conclude that the use of chemical additives and heterofermentative bacteria are justified to improve AS of high moisture grain silages.
