I have one thats 27 YO and mean and nippy as ever.
The trick to a healthy bird is feed it table scraps like chicken , rice, eggs, etc. My Vet 27 years ago said feed the bird anything you eat unless its overly greasy or salty or contains chocolate. He also get a good seed mix and carrots the only veggy he will eat. My bird has NEVER been sick in 27 years. I was told Senegals live to be 30-35 years on average.