In my experience, feed stored in my house at room temperature is good up to 5 months, before I see a drop in egg production.
Within 2 days of dumping out the old feed, washing the feeder,
View attachment 1417190 , and filling with feed less than a month old,
View attachment 1417191 ,egg production was back on track.
This is the feed I removed,
View attachment 1417192 . It was dry, not moldy, but it had an off smell to it, not grainy like the new bag I opened.
So feed may look good, but smell bad.
Moral of the story, don't buy a 40 or 50 pound bag if you can't use it within 5 months of mill date. GC
Edited to add; So learning to read the date code is important.
Some like Nutrena Naturewise have an easy to understand date on the tag; MFG:11DEC17.
I am now feeding Non-Medicated Start & Grow in 25# bags, with Oyster Shells on the side.