Zoetis Dectomax (Doramectin) Pour-On is used for the treatment and control of various species of gastrointestinal roundworms, lungworms, eyeworms, grubs, lice, horn flies and mange mites. Its weatherproof formula won't wash off in the rain. Controls 33 stages of internal and external parasites with a single, convenient application. Dosage is 1 mL (5 mg doramectin) per 22 lb. body weight applied topically. Proved to effectively control infections and to protect cattle from reinfection with Cooperia oncophora and Ostertagia ostertagi for 28 days; and Cooperia punctata for 35 days after treatment.