I guess this isn't a problem a lot of people are having, especially at this time of the year as it's winter in the Northern Hemisphere. However, it is the middle of summer here in Australia and it was forty-three degrees today for me. I rather quickly discovered this isn't a good temperature during hatching - the inside of the incubator is six degrees cooler than the outside! I've had nine chicks die of hyperthermia in the past two days (there are about 25/30 more who are fine, though). So much for keeping chicks under a heat lamp until how many weeks of age - mine are going under a fan. I'm not sure exactly how to treat hyperthermia in poultry, but here's what I've been doing. I've saved three this way. First, make sure the chick is still alive. Hopefully it will respond when you touch it or pick it up. Then assess the condition: Floppy, tries to lift head, panting - good. Proceed. Floppy, doesn't respond to touch, breathing slowly - not quite so good. Proceed. Floppy, doesn't move, panting or breathing slowly with mouth full of clear goop - bad news, probably almost dead. Floppy, not breathing, doesn't move - probably dead. Bad news. Stiff, not breathing, doesn't move - definitely dead. Options four and five are very bad news, obviously. Option three is also bad, as the chick will probably die within seconds. It's very difficult cool them down in time, and impossible to rehydrate them. Options one and two are good. Well, not good, given the chick has heat exhaustion, but at least you can do something about it. First, I take the chick to a cooler place, hopefully right in front of a fan. I fill a teat pipette with cool water. Not cold, but cool - normal room temperature, if you ignore that the room's probably about 45 degrees. Put a drop on the side of the chick's beak - it should open and shut the beak a few times to swallow the water. Keep going. The chick will want to keep taking in water, but be careful and don't give it too much, or you'll move straight to Option Three and then quickly to Option Four. Stop after a couple of drops and hold chick in front of a fan, rotation and turning so that it gets cooled all over. Feed it some water again. Repeat. Be careful not to keep the chick in front of the fan for too long, or you'll risk the other extreme, hypothermia - equally bad news, but somewhat easier to treat. Just keep the chick in front of the fan until it's a more normal temperature - slightly warm to the touch. Remember chickens have a higher body temperature than humans, so if it's cold to the touch it might be hypothermic. But you shouldn't feel like your fingers are going to burn off when you touch it (which it probably felt like when you began). Once the chick is looking perkier and feels a more reasonably temperature, I usually keep it with me for a bit to keep an eye on it, continuing to feed it water when it begins to pant. I don't cradle it against my body - it would be too hot, unless I'm in a cold room. A room about 37 degrees is good - the same as an incubator. If your house is colder, feel free to hold the chick against your body, but it probably wouldn't be hyperthermic in the first place then. After a while, the chick should start acting normal again, sitting up and walking around and chirping lonesomely. Feel free to put it back in the brooder. Continue to monitor brooder temperature. If anyone has a better, more successful method of treating hyperthermia, please tell me. This works most of the time for Options One and Two. Most of the ones I've lost have already been in Options Three to Five before I got to them. Hyperthermia sets in very quickly.