No more eggs; heat or feed change?

[amama]

We have 15 hens (Australorps are 2 yrs, Dominiques are 1 yr), and 15 chicks (about 15 weeks old).
My hens were laying well, about 11 eggs daily, until after around the time we added the chicks. Things started slowing down, and now they aren't laying anymore except for my Dominiques, so 2 eggs a day Which means I'm feeding them an awful lot this year for them to lay only in the spring, as they'll be molting this fall.

We haven't had chicks until this year (I've always purchased pullets ready to lay) and since they are all free range together, I switched the layer feed to All Flock feed. They still have free choice oyster and grit out. Could that have stopped the laying, or is it from the heat, or something else?

We've had a really hot summer, but they have a lot of shade choices on our acreage, and always have water in the shade. We give them sprinkles from the hose as well sometimes, some like it, most don't

Anyways, I don't see how I could feed them separately if it's a feed issue, but I read chicks shouldn't have layer feed until about 22 weeks?

Is there anything I can do to get them to lay again?
Thanks

 

[mixedbreeds]

Mine have dropped way down in egg production with the high temps only getting around 35 to 40 eggs from 75 chickens started dropping when the heat got in the high 90s. I have always started feeding layer crumbles when the new girls started laying most of the time that was around 16 to 18 weeks old. Happy chickening