I don't have sources, nor do I claim to know all. I merely stated something I believe to be a possibility, the OP can do with that as they want. As for the sources you linked, I did read through all of them and I appreciate you linking them. I am not an advanced chicken keeper myself so I do not have a lot of experience on the specific topic, so I love the opportunity to learn and be proven wrong. I actually really enjoy it. I do however, like to think my understanding of biology has some value. If nature does something, it's typically for a reason. There are almost always workarounds, but that doesn't always mean they're flawless.
For your sources, only the first one from The Chicken Chick even addresses long term affects of unnatural lighting on hens. I enjoy Dr. Petrik's information on that page, it does have a lot of substance to it and the blind chicken experiment sounds totally neat, aside from creating genetically blind chickens of course. But aside from that, there's still not much substantial proof whether it does or does not effect lifespan or egg laying, just a claim that there is not enough evidence to suggest it does. He does, however, address what was kind of my overall point-- it is vital to at some time (he says every 12-18 months) give the chicken a chance to stop laying and molt as it is physically beneficial to her health. And for the lifetime supply of eggs in the ovaries comment, that doesn't really prove anything either. I'm under the impression most female animals, if not all, are born with all of the eggs they will ever have in their life, humans included. That doesn't mean they'll use them all-- he even says the hen will stop laying of old age before using them all. The question is whether or not old age comes sooner to a bird that has essentially put more effort into producing more eggs, or nearly nonstop eggs, during her lifetime. I'm not trying to deny his claims, I'm just saying there isn't much proof in that article that things are one way or another, just someone's word. Peer reviewed studies on this topic would be awesome to see.
As for the other two sources, neither really seems to address long term affects of unnatural lighting on hens, at least, not that I could find and I read them pretty thoroughly. They mostly describe how to use the best lights, the best methods, and the best timings to maximize the number of eggs you get out of your chicken. The second source does address the benefits of a slow introduction into egg laying for young pullets as it helps physiological development of the bird and can possibly make them less prone to prolapse, but that's the only connection to health that I found in either of them. So while full of great information if you do want to get more eggs out of your birds (actually the Lewis et al. study mentioned in the UCONN source is totally interesting-- exposing pullets to an increase in light between the ages of 9-12 weeks will have more of an effect on their overall sensitivity to photoperiod changes than if they were only exposed after 18 weeks), they really don't do much to prove my above point one way or the other.
EDIT-- And just to reaffirm this for the OP, because I did not intend for this thread to discuss lighting, feed still won't affect laying, it will just make it easier on the hens when they do lay.
