It appears to me to be mucus or mouth rot. I've seen it before and although it can be difficult to treat, you can start by cleaning it out with a cotton swab and applying diluted peroxide to the area. After cleaning it with the peroxide, use another swab to apply a thin coating of Neosporin or any triple anti-biotic ointment. Do not use the cream ointment. It should be cleaned once a day. Keep an eye on it and if symptoms do not get better within a few days, I would advise a vet visit as Cathy did. As she mentioned, symptoms are usually caused by another underlying condition. A slight RI has been known to cause stomatisis or excess mucus around the mouth. This can also cause the teeth to become loose.

Good luck.
Brandon
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