It is mixed the present invention relates to the micro constitutent that soluble container is used for animal feed, method and using in this soluble container with preparing animal feed. Ingredient needs are very small amount of, relative to the animal feed of remaining ingredient, it is, micro constitutent, can be predetermined amount and is sealed in soluble container, and it can be by soluble polymeric films, it is the preparation when complete animal feed that other feed ingredients, which are then added,.