Die Bodenkultur - Journal for Land Management, Food and Environment

A. Adler, C. Berger, J. Neuhauser and H. Lew:

Quantitative changes of epiphytic lactic acid bacteria on forage in the course of harvest and ensilage

Summary

Quantitative changes of epiphytic micro-organisms on forage in the course of harvest as well as during the ensilage process were studied. In further investigations the quality of silages made of mowed and of chopped plant material respectively was compared. The results of the study revealed that the method of harvest did not significantly affect the counts of aerobic bacteria, clostridia, yeasts and molds. On the other hand an immediate increase in numbers of lactic acid bacteria (LAB) during the harvesting procedure was observed. Chopping enhanced the recovery of LAB during the important early stage of fermentation and caused a more rapid decline in pH compared to the corresponding mowed material. The higher metabolic activity of the LAB in the chopped material resulted in an improved ratio of silage acids as well as in a reduced loss of dry matter and net energy during silage preservation. More intensive mechanical treatment brought about favourable microbial conditions for a desirable fermentation and a successful silage preservation. The favourable effect of the release of juice and cell contents from the ruptured plant material apparently exceeded the advantage of the compact consolidation during ensilage. Key words:  Forage, silage, lactic acid bacteria, conservation.