Dog Vomiting Yellow Foam Slime. Food allergies and intolerances are also a cause of yellow vomiting. Yellow vomit may suggest that dog raising a fluid called bile.

Your dog might be throwing up yellow foam or yellow slime called mucus. In the case of bilious vomiting syndrome, the empty stomach causes bile to irritate your dog’s digestive tract; Dog vomit can be different colors depending on the contents of your dog’s stomach, how recently your dog has eaten, and the presence of bile in the vomit.