and apparently there is an interesting article about it:Originally Posted By: Chloe's MommyI have a friend in Israel that just puts a small cup (like for a child's syrup) of apple vinegar (or any other vinegar for that matter) in the drinking water. She has 6 dogs, all with long-ish coats (Westies) that are constantly playing outside and going for walks in the forest, and not one flea of tick on them.