There is a natural genetic mutation that has been found in chickens that render them blind. This mutation, can be bred so that offsprings of the blind chickens will be blind as well. Now, fortunately enough, blind chickens are less stressed by overcrowded conditions, since they can't see. So these blind chickens can be raised in normal factory farm conditions without experiencing the same anxiety as normally sighted chickens do.
Should we breed blind chickens so that we can raise them in closer quarters?
Note that these chickens are born blind. They haven't been robbed of anything.... they never had it to begin with. If we don't breed these chickens, the alternative is that some other chicken will exist, that can see, and suffer more, than the chicken that is blind. And as much of an optimist as I am, I don't believe that factory farming will go away any time soon, so simply appealing to eliminate factory farms is naive at best. It would not take much to replace the chickens we have, with blind chickens, but it would take much more effort to redesign the way we farm chickens. So from a practical perspective, this is a way we can reduce the suffering of chickens immediately.