Our atiel is healthy and loves meat. His favorite is chicken, shrimp tails and oysters. Hope it is ok?

No, he should not be eating shrimp and oysters. They have higher levels of bacteria and can kill your tiel :( Please don't feed him those anymore. I've heard of them eating chicken which just seems so cannabilistic and wrong but I can't think of a good reason that fully cooked, fresh chicken would be bad. I wouldn't overdo it though. My atiels are really picky. I wish they would eat more food. The only thing they really love is carrots, shredded into tiny pieces.