I had a lecture from a fellow dog walker yesterday about 'poisoning' my dogs with monthly parasite treatment. She uses garlic, apple vinegar and other natural things to prevent parasites. I was quite dismissive but now I'm wondering if I was too hasty? I don't want flea infestations or my dogs to suffer from the effects of things like lung worm, but equally I don't want to overload my dogs with dogs toxic nasties.