I have been feeding all three of my dogs Royal Canin Chihuahua for about a year. A few weeks ago my border terrier tested positive for and was treated for a urinary tract infection. I took in a second urine sample a few days ago which showed his infection had cleared up. This morning there was a alot of pee on the ground again so I tried taking in a sample for my chihuahua and my brussels griffin. The Brussels has a slight infection and the chihuahua has a very bad infection. The only thing that they all have in common is their food. Has anyone else had a similar experience? What would be the best food to put them on? My brussels is now on antibiotics for 10 days and by chihuahua for 14 days. I will have them retested at the end of the treatment.