pour-on for treatment and control of parasites in cattle. effective against roundworms, lungworms, grubs, horn flies, sucking and biting lice, and sarcoptic mange mites. cattle wormer is rain-fast six hours after application. Apply the pour on to cattle along the topline in a narrow strip extending from the withers to the tailhead. Use of the pour on cattle wormer is safe for pregnant cows. Use it at the rate of 1 ml per 22 lbs. body weight.