Hello. I was told today that I can use my Ivomec Pour On for my dog to treat for fleas, parasites and heartworms: Is this true? Does anyone know? I know the injectable kind you can but what about the pour on. I do not have a collie, nor herding dog, so no worries there. If I can use it on him, great. It is purely preventative but Heartgard is way overpriced and if this kills other parasites too WONDERFUL!!! Does any one know how many drops on the back to do and if it's safe?