to the forums!
I'm sorry to hear that Shu's cere has turned brown
In males, that indicates either a hormone imbalance, or possibly testicular cancer. His diet seems to be healthy, and it's good that he eats his greens as that can help a lot
First thing, I would get him checked out at a vet because it's best to catch these things before they progress further. In the meantime, milk thistle and dandilion root work well with fighting potential cancer or similar problems, as well as to detoxify the liver in case the problem is there. You can buy both these supplements at a health food store.
He sounds very healthy and although he's reaching old age, I think he's a strong little fellow and surely will pull through
We'd love to see even more pictures of him in the future because he is a very
handsome little man! Please keep us updated and let us know what the avian vet says when you're able to get him into an appointment. It's always better to let trained professionals diagnose problems like this so you know how to treat it with the greatest accuracy.
It's great to have you with us and please do ask about anything you're concerned about as we're always here to help.
Hope to see you around!