It get up to the high 40s C (104f -118F) on average here in summer and have never lost one. I do have large trees they can go under if they want some shade alot of the time they seem not to mind the heat.
Here in australia in summer it gets really hot and humib. I half freeze plastic drinking bottles and top them up with cold water. Leave them around the place and they will actually go and sit on them if it gets too hot. The bottles are for them to sit on etc not drink.