The invention relates to a biological
enhancer for
ruminant feeds, and a preparation method for the biological
enhancer. The biological
enhancer comprises the following steps: (a) preparing a
fermentation medium, and crushing and mixing 85 to 95 weight percent of a
carbon source, 1 to 2 weight percent of a
nitrogen source, 1 to 3 weight percent of a growth
promoter and the balance of water for later use; (b) inoculating candida utilis into the
fermentation medium obtained in step (a), and performing
solid fermentation cultivation; (c) inoculating
lactobacillus plantarum into the fermentation medium obtained in step (b), performing anaerobic
solid fermentation cultivation, and performing sampling for OD600 at a time interval of 4h; (d) when OD600 enters an exponential phase, inoculating
bacillus subtilis into the fermentation medium obtained in step (c), and performing
solid fermentation cultivation. The biological feeds prepared according to the method have the advantages that the microecological balance of rumens of ruminants can be improved, the feed conversion rate can be increased, the
immunity of the
organism can be improved, and the products have special sour and sweet smell and high
palatability, and are easy for animals to ingest.