On the label of ivermectin pour on it should give a strength. 5 milligrams per milliliter (or 5mg per ml) is a common strength. Dosage of that strength is 0.045 or rounded off to 0.5 ml per pound of weight is used on the back of a chicken’s neck once, and repeated in 14 days. It can treat lice or mites. It is not a good choice for worming however.What does 5mg/ml mean