Is it medicated in any manner? If not the biggest difference will be the protein content, you will not have an ideal mix (how much protein is in it depends on the actual mix, it falls in an overlapping distribution with chicken feed) in all likelyhood but given enough free ranging you probably will not notice any drawbacks. If it is medicated it will depend on the type of medication used.

I should have said game bird starter. yes it is medicated

Can you list the medications? In most cases I would expect them to be fine, but I don't know that for a fact.

well really I meant to ask if anyone has fed the game bird feed to chickens and if there were any adverse effects. I had to go out in the barn and find my glasses to read that timy print in order to tell you what was in it. Then came in and found it on the internet. And looking at the label it looks like it is not medicated even though I told them I wanted medicated. seech,,,

Here is a link that might be useful: Purina Game Bird Chow

If it is medicated then don't feed it as you'll have residue in the eggs. Otherwise it's fine. Chickens will do better with a higher protein but only NEED the 16% that is in most rations. More protein means more eggs and better fertility if you are breeding them and also allows you to feed more lesser quality scraps without compromising nutrition.

fancifowl that sounds good.
I wrote a bunch of people about this question since the forum is pretty much dead these days. Here is the response I got back:

Generally game bird starter is not recommended for chickens. It is higher in protein than they optimally need, so they may grow very large faster than is good for them... or they can have a lot of extra energy which may cause them to have some aggression. If they have a very large space, they may be able to work off that extra energy. if their brooder is small, you may face some management problems. There is nothing inherently bad about feeding chickens game bird feed other than that possibility. When they begin to lay, though, it will be best to have them on layer mash or pellets because it will have enough calcium for a laying chicken's needs.

Do you have any problems with aggression? What about hyper energy?
Thanks

I put a good hay in the bottom of my chickens pens they get a good workout scratching for the food gives them an activity