A 17-year-old female tiger has died at the Louisville Zoo.Sinda the Amur Tiger was diagnosed with squamous cell carcinoma in the roof of her mouth in September. Curator Steve Wing says zoo officials consulted several vets and other doctors, all of whom determined the cancer was inoperable."We kept an eye on her, all this time, and gave her some extra attention, she was on some medications and things like that. And unfortunately it just progressed to the point where we needed to euthanize he," says Wing.Sinda arrived at the Louisville Zoo nearly ten years ago, and was mother of two cubs born in 2004.