Although you may not think it, your chickens can overheat, making them lay fewer eggs, eat less, drink more, have loose stools, also they can become more aggressive. Chickens can't sweat like us humans, nor can they easily remove their fur jackets, so it is essential for us to help them cool down.
A shallow pool of water is the perfect way of cooling down your chickens as their feet and legs are one of the best areas to reduce their core temperature. Chickens can contract heat stroke, if they are looking pale and begin 'panting' you can dunk them into cool water for a minute or two up to their neck if necessary. Gently towel pat the feathers and leave them to dry in a shaded area.
You can create a shaded area by simply covering a section of the coop and run with a towel/tarp or something similar. This simple measure will not only reduce the temperature of the coop and provide shade and protection from the sun, but also bad weather.
Chickens 'dust bathe' to reduce parasites/flies and to cool themselves down on hot days. After a period of no rain, the layers of dirt become dry and hot, to help cool them down use a watering can to water their dust/mud area so it is cool and damp.
Inside the coop can become too hot for even humans to handle if you don't keep on top of cleaning during hot weather. The decomposing of chickens faeces creates heat, it also attracts flies and insects into the coop which can cause 'fly-strike' on your hens and the ammonia fumes can become intolerable. Changing bedding frequently and leaving no more than a couple of inches is fine for the summer. Also providing or improving ventilation is a great way to keep a cool breeze flowing through the coop. If you have lights, we would suggest you kept them off during the day as this also contributes to the heat.
Feed & Water
In hot weather, chickens will drink up to 3 times more water than usual. so keeping their water fresh, clean and cool is an important way to keep them healthy. Their feed intake will notably drop as will egg laying, so keeping them hydrated with cold water is important. To keep the water cold you can add ice to the drinkers and place somewhere they will not be getting hit by direct sunlight.
A favourite treat for your chickens with natural sugars and plenty of water is Watermelon! You can feed it whole or blend it and place in the freezer for a couple of hours for extra hot days.