Preparation method of composite feed additive and anti-virus agent and application of anti-virus agent

The invention discloses a preparation method of a composite feed additive and the composite feed additive prepared with the preparation method, further discloses a method for preparing an anti-virus agent from the composite feed additive, and the anti-virus agent, and further discloses application of the anti-virus agent in inhibiting vesicular stomatitis viruses and application in preventing animal cells from infection of the vesicular stomatitis viruses. The invention has the beneficial effects that 1, due to mixing and fermentation of two bacteria, namely brewer's yeast and methyl nutritional type bacillus, the composite feed additive is relatively rich in nutrient component and active bacterium, is capable of greatly improving the disease resistance of animals, and has great significances in livestock feeding and feed industry; 2, the anti-virus agent is a composite feed additive lixivium, and has remarkable activity and proliferation inhibition upon VSVs (Vesicular Stomatitis Viruses); 3, the anti-virus