Dead Barred Rock-Heat Stroke?

[RockyComfort]

We had nine hens that are laying, 3 Barred Rocks, 3 Easter Eggers, & 3 Cinnamon Queens that are just about 6 mo old. They all seemed healthy and happy but we went out today and one of the Barred Rocks had died. We are wondering if the heat may of been a factor. We have had a heat advisory in effect for the last week and it was 107 heat index yesterday. Could she have overheated? Has any one else had this happen in instances of extreme heat? The only thing thats that we have fed them besides layer pellets is, grass, bread, tomatoes, sage, and mint. I am pretty sure that these are all safe but if not please let me know! I appreciate any feedback or advise.

 

[lovemy6hens]

We have 7 hens. Our barred rock has always seemed more sensitive to the heat. Two days ago, she was the only one on the verge of heat stroke (I believe her emergency bath in cool water saved her). Perhaps it's the breed?

 

[Eggcessive]

I would make sure they have extra water stations, and put out at least 1 flat pan of shaded water for them to cool their legs in. On the very hottest days I will add a vitamin and electrolyte mix to the water. There are many brands such as SaveAChick and the one below: