Report Jess has horrible breath. in General Border Collie Discussion Posted February 17 1 hour ago, gcv-border said: The first thing I would do is check her teeth. Are they clean or do they have tartar on them? Depending on how dirty they are, you could get her checked out soon by a vet, or if they aren't too bad, try attacking the problem yourself until Jessie's next check-up and make sure you have a conversation with your vet about her teeth and bad breath. In the short term, I would consider getting a doggie toothbrush and toothpaste and trying to brush them. Also, (as recommended to me by a vet), give her a Virbac C.E.T. Enzymatic dog chew once a week. She says her dogs' teeth have never been so clean. I just started using them so can not provide a review. Other people use raw, meaty bones once a week or so to keep the dog's teeth clean. It may be something else, but I would start with checking out her teeth. Thank you, will go shopping.