https://www.nutrenaworld.com/product/naturewise-feather-fixer-poultry-feed
I had my hens on this a few months before collecting eggs to incubate. Is it a decent choice?
Looks decent, though you'll note the guaranteed analysis ignores B(any sort) and K. B is water-soluble, so it is often left out of feeds that have oil. Riboflavin is the most common deficiency in layer feed.
It can be found in spinach, dandelions (I think?) and strawberries.
Honestly, I would just buy some vitamin B complex tablets and supplement. They're cheap. Make sure they're low-to-no iron.
EDT: nice protein content, though.
Im curious about your incubator too, and what humidity you had for lockdown. Ive only had the really thick white inner membrane on one chick before. it was a malpossition that died on day 22. I was having a really bad time with malpossitions in that batch but none of the others had that. I just assumed it must have been because the chick had died before i tried to help.
