Bacterial and fungal microbiota of total mixed ration silage stored at various temperatures

To obtain insights into how bacterial and fungal microbiota and fermentation products composition are affected by storage temperature for TMR silage, which can be manufactured year-round.

TMR silage was stored at 10°C, 25°C, ambient temperature (AT; 20-35°C) and 40°C. Lactic acid production was delayed when stored at 10°C, and acid production stagnated after 2 weeks when stored at 40°C. The patterns of acetic acid and ethanol production were inversely related, with ethanol production promoted at 10°C and 25°C and acetic acid production promoted at AT and 40°C. The bacterial diversity was reduced in TMR silage with high lactic acid and acetic acid content, and the fungal diversity was reduced in TMR silage with high ethanol content.

The intensity of lactic acid production was accounted for by the high abundance of Lactobacillus, and its stagnated production at a substantially high storage temperature was related to an increased abundance of Bacillus. The enhanced production of acetic acid or ethanol can be explained by differences in the fungal microbiota.

The integrated analysis of bacterial and fungal microbiota can provide in-depth insights into the impact of storage temperature on TMR silage fermentation.