My 13 yr. old dsh in 2 days developed a serious breathing problem. He will meow loudly, get on the floor and mouth breath with a Very high breath rate. My vet took a chest film, it was inconclusive. He drew a little blood from the right side near his lung. He was expecting a yellowish fluid and a diagnosis of FIP. He was very honest and said he had no clue what the problem was. He injected him with penicillin and cortizone and gave me liquid amoxicillin to give to him, on the chance it might be bacterial in nature. When he is not having these mouth breathing attacks, he lies straight and his breathing is labored. He won't last much longer like this! Any ideas I can give my vet. Any help will be appreciated. Thank you all so much. Bill