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

Aims 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. Methods and results TMR silage was stored at 10 degrees C, 25 degrees C, ambient temperature (AT; 20-35 degrees C) and 40 degrees C. Lactic acid production was delayed when stored at 10 degrees C, and acid production stagnated after 2 weeks when stored at 40 degrees C. The patterns of acetic acid and ethanol production were inversely related, with ethanol production promoted at 10 degrees C and 25 degrees C and acetic acid production promoted at AT and 40 degrees 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. Conclusions 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. Significance and Impact of the Study The integrated analysis of bacterial and fungal microbiota can provide in-depth insights into the impact of storage temperature on TMR silage fermentation.

Automated summary

Storage temperature has a significant impact on the bacterial and fungal microbiota and fermentation products composition of TMR silage. Lactic acid and acetic acid production are inhibited at high temperatures, while ethanol production increases. High lactic acid and acetic acid content in TMR silage reduces bacterial diversity, while high ethanol content reduces fungal diversity.