I use Manna Pro All Flock. Of all the feeds I've fed over the years, this brand is liked by my birds more than any other. It may not work for large flocks as it comes in 8 pound bags. However for small mixed or older hens no longer laying, its a wonderful feed!
https://www.mannapro.com/products/poultry/adult-poultry-care/16-all-flock-crumbles-probiotic
https://www.mannapro.com/products/poultry/adult-poultry-care/16-all-flock-crumbles-probiotic