My comment on one of the chicken threads: (with regards to comparing feed tags from years ago to current feed tags in case formulations changed and the same feed decreased in quality)
"There's also just the fact that not all feed/brands are created equally or the same quality. I hate to bring up dog food as an example but its the same thing. Some are higher quality than others. Find a food your birds do well on and feed that. And if you feed the cheapest stuff you can find, when other factors change (such as winter, less daylight, colder weather, molting, etc) you might see a change in egg laying. I'd say its not rocket science, but it is apparently LOL. I say this with feed labels piled up on my desk next to my coffee this morning because I'm a data nerd and already do this sort of research for my dogs. Why not do it for my birds too.? I typically feed a variety, because yes some of the "cheaper" stuff is more affordable but I do think my birds do better on better food. But... not tinfoil hat stuff."