When sourcing Tiamulin, buyers must prioritize pharmaceutical-grade purity, typically requiring a content of not less than 98.0% on a dried basis. It is essential to verify that the product complies with international pharmacopoeia standards such as USP (United States Pharmacopeia), EP (European Pharmacopoeia), or BP (British Pharmacopoeia). Key indicators include loss on drying (≤0.5%), residue on ignition (≤0.1%), and specific heavy metal limits. For feed-grade applications, ensure the granularity and flowability are optimized for uniform mixing in premixes.