Not if they can regrow hair cells, which is one of the main areas of research right now. Did you know that Chickens have hearing that heals itself? Yep. Chickens can go deaf and then naturally repair themselves (like a bruise or scrape) and hear again. It's all about the regeneration of hair cells. Just Google "chickens hair cell tinnitus" and have a look see. Lots of hope in that area of research. If only the wacky religious people would let scientists use embryonic hair cells it would go much faster.