Last July I had some baby chicks shipped in from a hatchery. They had an option for 'one free chick' and unfortunately I took them up on it. It ended up being a polish rooster, which is a breed with an elaborate head dress of feathers.
The problem arose when I introduced the new chickens into the pen with the old chickens. He looked different so they picked on him brutally. The long feathers on top of his head were easy to grab and hold onto so he didn't do so well. One day he trapped himself in a corner and couldn't get out and was pretty beat up.
I moved him into my brooder box, which is a 4x6x3 plywood boy with a hardwire top, for his protection. I noticed he was startled whenever I touched him, but I assumed it was shell shock from the beatings, or those stupid feathers were blocking his vision where he couldn't see anything to the side or behind him. After a couple days I was a bit suspicious, so I really inspected him. He is blind in both eyes. I don't know if it was a birth defect or from the other chickens, but he can't see regardless.
So now my problem, I have 3 options and I don't know which is the least cruel.
I can leave things as they are and let him live out his days, but I don't know how humane that is since chickens are social animals and he is in a little box by himself.
I can put him back in the pen with the other chickens, and let nature take its course. He would be pretty much defenseless.
Kill him. He is too small to be worth eating.
Some additional information:
He seemed to be doing fine until a month or so ago. He used to crow whenever I went out to the shop and seemed pretty content with his situation. I had a hen that was getting pretty beat up in the big pen, so I put her in there with him to rest and heal. I left her a couple weeks with him but moved her back to the pen once she was better. She was getting restless in the confines of the brooder. Ever since then he seems more and more lethargic. He now just sits on the roost in the box, never crows, barely eats or drinks. I am just no sure what is the best course of action.
My grandparents had a farm with a shit ton of chickens when I was younger. I'm not sure how the older ones were killed because they were a rarity, most were sent off when they were around 6 weeks old.But he would just pull/snap their necks and they would die pretty much instantly. My advice would be to kill it. I have watched my grandad kill hundreds of them, partly because the small ones are not worth keeping to sell, but also because they do not have a great experience while they are still alive with the others.