When do chicks not need heat lamp?

[Chicken101-07]

I have 8 chicks,5 bought from TSC which were supposed to be 1 day old but they are not,the other 3 are younger and are 5 days old,can I separate the older ones?I have the temperature in the low 90's and this seems to be affecting the 5 bigger ones,they are always with their beaks open as if they were overheating while the 3 little ones are normal,I'm afraid im going to overheat the big ones or kill the little ones if I drop the temperature too much,the poop of the bigger ones is also causing quite a smell even with the pine shavings,the big ones are broilers chickens,their wings have pretty much feathers and their tails are forming,is it safe to move this big ones out of the brooder and leave the little ones for a while by themselves?temperatures are at high 70's outside,I will move them to a cage inside the coop.

 

[Chickenhappy8708]

Concentrate it to one area, so the older ones can get away. That should help them.

 

[Willow2253]

Make sure you have a heat gradient, so you have the heat source at one end of the brooder and cooler at the other end. You can overheat even the little ones if they don’t have an area to cool down. Once chicks are fully feathered you can remove heat, but they won’t be able to maintain body heat well enough before then to not provide any.

 

[rosemarythyme]

I'd consider separating out the broilers entirely, they'll grow much faster than the other chicks and can accidentally crush or trample them.