Unexplained weight loss
My 8yr old male went on an 8hr walkabout in Nat Forest mid April with his GSD housemate. Within 9 days he lost 5lbs. He cannot gain weight. Been tested for everything, xrayed and ultrasounded. Now on doxycycline for possible upper respr that I think was really allergy response and tylan because specialist thinks it could be SIBO or EPI altho tests say no. Also getting weekly B12 injections.
Vets tried metronizadole and sucralfate in May.
He has remained full of energy with no diarrhea or vomiting. Only symptom is weight loss and no gain. He is a raw fed dog. I keep hoping at every weigh-in he shows a gain. His walkabout GSD housemate shows no sign of health problems. Any ideas?