Yes, I was aware of the study, and commented on it in the other thread. I won't repeat those comments here.I'm cleaning rabbits and guinea pigs right now so I will give better response later, hopefully. I'm not certain that I am qualified to judge. I am asking questions, researching and learning as a first-time chicken mama. I have been carefully reading labels on all of my animal feed and also my own, and honestly I'm horrified, esp after reading the conditions of and what is fed to most commercially raised chickens and cattle. Guinea pig and rabbit food is loaded with fillers and preservatives in most cases. Whatever the chickens eat passes to us through their eggs, right? I am not good with a heavy corn and soy diet for myself. Most corn and soy are GMO in US, so I question the reliability of food that says organic and non-GMO, esp if they don't provide the source of the ingredients. I understand that dietary requirements for chickens are different than my own, still I am continually looking for better or the best options. I also know that all the contradictory opinions about chicken feeding in blogs and other articles are just opinions and not based in research or fact so I double and triple check. I put a post about feeding chickens charcoal mixed with apple cider vinegar and everyone poo pooed me, but this information was verified by scientific studies on a government website https://pubmed.ncbi.nlm.nih.gov/23972401/ which you can check out. Ok. I'm out until later. The natives are getting restless.
No, what chickens eat does not, necessarily, pass thru their gut and into the egg. Very little does, intact, in fact.
Personally, I look for Soy in feed for chickens - as a legume, its one of the few decent vegitative sources for Methionine, which is a critical limiting amino acid, particularly in developing/growing birds - good sources are so rare, in fact, that synthetic methionine (limited by regulation) can be added to "Organic" animal feeds, and still maintain its Organic status.
If you have questions regarding sourcing, you can absolutely contact the company making the claims regarding it. It is HIGHLY regulated here in the US, so much so that it serves asbarrier to entry by small farmers, even those who would be "Organic" and "non-GMO" by practice, except in the matter of recordkeeping. Litigation over false claims is HIGHLY lucrative- its grounded in fraud and typically involves statutuory, rather than actual damages, often includes amultiplier where actual damages are shown, and finally - contra the "American Rule" - often provides fee shifting to the Attorney of the one bringing the claim, if successful.
The history of human farming is one of carefully selecting desired genetics. I'm sure you've seen the broccoli poster, but if not -
All the results of carefully selecting for desired mutations and the culling of undesired traits. That a thing is modified, in and of itself, is not concerning. Even "Round-Up Ready" plants aren't a concern in and of itself, the concern is that a Round Up ready crop encourages use of glyphoshates, which are of concern. Or perhaps you select for non-GMO because labels don't currently distinguishbetween organisms modified by man, and those modified by man with DNA alien to themselves - such as the way many synthetic amino acids are now produced, and thousands of other useful substances besides.
As to non gmo-Soy? Depends on who you ask. The Soy Export Council claims its about 50%, and they should know. Of course, the USDA says otherwise. It seems like both can't be true, but perhaps USDA is speaking about all planted food grade soy, while US SEC is refering to all soy (food grade and non) destined for export. I can appreciate some frustration in finding hard data.
In any event, what you find in chicken feed will vary by manufacturer - and its often the most expensive feeds that have the most odd-ball ingredients, many of dubious value. I commend you for reading labels, but that's only a necessary pre-condition. Each ingredient you find there must then be researched on its own. Why is it there, what benefit does it offer, what concerns does it bring with it?
Good luck in your research efforts.