I just had a thought on nutrition (starting reading @KikisGirls links, thank you!)
Since October, I have been throwing LOTS of seed to grow pasture, which I mow like a lawn. By lots, I mean pounds. Pounds and pounds and pounds. Lots of grass seed (various rye grass, Kentucky blue grass, various fescues, etc.) along with a chicken forage blend (ryegrass, clover, alfalfa, flax, field peas, groats) and additional clover, flax and alfalfa. The girls LOVE the fresh, delicate sprouts I have all over the yard all the time.
HOWEVER, they also eat a bunch of the unsprouted seed. I see now this could pose a nutritional problem. Thoughts?
In case it helps in analyzing, they go through about 50 pounds of organic soy-corn free (22% protein) feed about every two weeks or so (flock of nine hens).

I am back to where I was thinking in the beginning...they are eating too many treats.
All the seeds are treats.