You really do need to get this poor baby to a vet ASAP. When they stop eating, it's a major and validating sign that something is for sure wrong. The open mouth and drooling is not normal at all. His mouth and that lump needs to be checked out thoroughly as that could def be the problem. *Please* get the dental work done - if you've ever had any amount of tooth pain, you should know just how excruciating it really is - that's no different for an animal
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