Heat Stress in Chickens

Heat stress is common in chickens in the warmer months in Australia. If their bodies warm up they struggle to cool themselves. You can minimise heat stress by ensuring they have a supply of cool water (not warm) and that they can get out of the sun and in a cool place such as under a shaky tree.

When the bird first gets heat stressed, they pant a lot trying to cool their body. They lose water in the breath trying to cool themselves by evaporation from the surface of the lungs. Excess waste acids are produced and build up, throwing the body's chemical balance off. Then birds drink a lot of plain water because they are hot and thirtsy and their metabolism works a lot faster. The amount of wet droppings increases and the diarrhoea speeds up the dehydration and the electrolyte imbalance. It's a vicious circle.

Heat stress is a form of shock, so sudden dunking isn't a good idea. You need to gradually get the body temperature down.

Once heat stress progresses you can end up with a bird that is in heat stroke and this is seriously life threatening.

The sort of symptoms you might see are:

gasping, panting, wings outstretched
Stupor, staggers and convulsions
Slowness and lethargy
Light body weight, poor colouring, rough skin

In treating a bird that is in heat stress or shock, the first priority is to cool the bird. Also electrolytes might be helpful. If you can get a bird into a cool air conditioned room, or even stand them in a bucket of cool water so their legs are in the water. In some cases wetting the bird and then resting it on a towel in the cool can help the body temperature to drop. The bird will need to be left in peace and quiet for a number of hours to recover.

You can use commercially made products, gastrolyte, gatorade, or even homemade. I would use the electrolytes only for 24 hours.

Homemade electrolyte recipe:
1 cup water
* 2 tsp sugar
* 1/8 tsp salt
* 1/8 tsp baking soda
Combine all ingredients and warm slightly.
Mix 1 teaspoon in one litre of water.

Bear in mind that even if seriously affected birds seem to recover, there may be organ damage that causes them to relapse a day or two later. They need to be kept cool and stress-free for a number of days to maximise their chance of recovery.

To show you what a chicken suffering minor heat stress looks like, here are some of my birds on a warm day suffering a bit from the heat. Nothing life-threatening - just experiencing some discomfort. The temperature was about 30C when I took these, but the humidity was really high. The sussex are especially uncomfortable in the heat. They go down to the little dam and stand in the water. I know they're starting to feel it when their wings are being held slightly away from their body and their beaks are open and they are panting trying to cool themselves. In this humidity evaporative cooling just doesn't work that well. These were taken about 9.00am and I put the hose over them shortly afterwards. They need to get used it because it's only going to get hotter.