my vet told me that you can't always detect intestinal parasites, I forget all the details but some of them are in casings and aren't detectable. Beck was having runny poop and the vet gave it 2 weeks to clear up, and said if it didn't she was going to treat him for parasites despite the negative tests. Fortunately we found a food that he does well on and have had no problems since. We also augment his kibble with home cooked chicken or turkey with rice, oatmeal and vegetables. Now he's got nice firm poopies
