We adopted Keystone from an animal shelter in June of 2008. Keystone started limping on his front right leg about 2 months ago, in August. I first treated him with Aspirin per my vets advice. After 2 weeks he wasn't getting better so I took him to the office. He was started on Prednisone which he took for 10 days. During those 10 days he started not to walk on his leg at all and would drag it on the ground. The Prednisone only seemed to exacerbate the problem. A second opinion at a different vet resulted in x-rays which showed extra growth in the bones of his shoulder. In the mean time he developed a harsh dry cough. The vet said the bone growth was due to an infection so we started giving him Doxycycline for the infection and the cough, which he is currently still supposed to be on but he won't take it. In the past 2 weeks he has lost 15 pounds, will not eat ANYTHING for a week now, can not see out of his right eye and has started craning his neck to left at all times, along with not walking on his leg still. He has zero muscle mass left in his right shoulder and is starting to get mildly aggressive. Any ideas that would cause these symptoms? He was previously healthy and had not had (to our knowledge) and previous infection.