Our 3 1/2 lb. Chihuahua Buddy is not feeling well and we have no idea what is wrong with him. We will be taking him to the vet early tomorrow. It started with lots of white foam being spit up (sorry for the details). We believe he is 18 years old, but he had been very active and his hearing was better than ours. He is drinking water, not eating, urination is fine, he can climb up steps. He is not acting like he is in any pain but he has no energy. We are feeding him chicken broth with a syringe. He just stays on the couch and won't go anywhere unless we take him to the water bowl or set him on the grass.
Any idea what may be going on?