If it were me...I would put starter in for when the chicks hatch. The hen will be fine eating the starter while the chicks are growing.
I'm feeding medicated chick starter to my one broody hen, the keet she has and the three tiny roosters with her. The chicks I moved into that pen had just started showing signs of coccidiosis prior to moving them out of the house. (I change out to new vinyl gloves prior to dealing with the house chicks and still managed to introduce it apparently.) So I changed to medicated. When I open the pen up they'll all be drinking the medicated water.
I feed 21% chick starter to the entire flock 100% of the time, free choice inside the coop. I feed grain outside; millet and wheat with screenings. It withstands rain if it gets rained on and gives them a variety. With the 21% protein of the chick starter...it should be in the vicinity of the protein provided in laying foods.
*I have seen someone post on BYC that too much protein can be detrimental for their kidneys. I haven't investigated that yet. I consulted a feed consultant and my vet last fall regarding what to feed the flock and whether chick starter could be an appropriate feed to feed 100% of the time. Both were worried about the egg shell quality more than anything. The vet explained that more urea would be excreted if the protein is higher. But then I feed a ton of grain in the winter for the cold weather so my protein shouldn't really be too high.
*If it's high, it's likely because I toss back so many raw eggs...but the starter I use is 100% veg protein and I want them to have an animal based protein.
Yup...that got a bit long.

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