They won't dispense heartworm pills without a test. I give my dog pills all year and don't believe I should have them tested if they have been getting preventative? I buy the pills from another vet but he is far away. My vet says they can still get heart worms even if on the pill. I say well then I will have them treated, but why have theme checked cause if they're going to get them then there is nothing else you can do and you will know soon enough if they need to be treated. Am I wrong?