Uniformity of content  in feed	The micro pure powder generally leads to static charge which makes active ingredients aggregate resulting the bad mixing uniformity of content in feed.
	The micro particle (the size is almost less than that of 80 meshes) with poor fluidity which makes active ingredients to  arc-bridge;
Stability  in storage	Due to large surface area exposed to medium, the active ingredients are easily attacked by moisture, metal ion, and acid/alkali ion, by which it would accelerate the potency decrease;
Stability in processing	Due to large surface area exposed to medium, the potency of active ingredients decrease quickly under high temperature and high humidity during the feed granulation process;
Side Effects on animals	Due to mixing non-uniformity ,the high-concentration part would irritates animal gastrointestinal mucosa;
	The undesirable taste of some drugs affect the palatability of feed greatly, which would reduce the feed intake;