Compound bacterium preparation and application thereof

The invention aims to provide a compound bacterium preparation and an application thereof. The compound bacterium preparation is a compound strain preparation which is derived from bacillus licheniformis, bacillus pumilus and bacillus subtilis in digestive tracts of prawns, wherein the bacterial strains are combined for use so that the immune level of cells and body fluid of the prawns can be enhanced; in particular, the anti-virus infection capability of the prawns can be improved. The compound bacterium preparation comprises bacillus licheniformis LV005 strains, bacillus pumilus LV012 strains and bacillus subtilis LV023 strains. The strains of the compound bacterium preparation are screened from the digestive tracts of the prawns, so that the compound bacterium preparation has the effects of improving composition and number of dominant bacterial communities of the digestive tracts of the prawns, forming and retaining good microecological balance of the digestive tracts, resisting adhesion and proliferation of viruses in the digestive tracts by competition for nutrients, competition for space or secretion of bacteriocin, improving non-specific immunity functions of the prawns by improving the activity of relevant immunoenzymes such as lysozyme and catalase of the prawns, and reducing the probability of virus infection.