As a pollution-free preparation that follows the law of ecological environment circulation,microecological preparations have the characteristics of high quality,non-toxic,ecological,no residue,no pathogenicity and have the same effect as antibiotics,etc.,and are gradually applied in various fields such as feed,pesticide,medical and health food.As a feed additive,microecological preparations have the effect of regulating intestinal function and rapidly building intestinal microecological balance,which can effectively improve the body condition of newborn livestock and poultry and facilitate the output of high-quality commodities.In this paper,the types and functions of microecological preparations and their application in the healthy breeding of cattle and sheep are discussed,which will provide reference for the future application of microecological preparations in ruminant production.