They call them the dog days. Those hot days of summer when the sun comes up bright and hot, burning the dew off of the grass just after it clears the horizon in the mornings. It gains strength as it steadily climbs until it hangs in the sky. White hot it begins toasting all green things until they are dry and brown. People do their best to escape its wrath, either by seeking deep shade, a cool drink and a breeze or through more modern means by ducking into the air conditioning. Animals suffer too. Large animals like cows or horses seek the shade and doze the hot hours away, but smaller animals often suffer the most. Small animals, like rabbits and chickens, can not sweat and are more sensitive to the heat.
In chickens and other poultry heat stress causes many problems including: a cessation of egg laying, stress related molt, dehydration, illness and frequently even death. Each year in the United States problems brought on by heat stress costs the poultry industry thousands of dollars due to losses in production and stock. In years of higher than average temperatures or drought those losses often result in higher costs and even shortages for the consumer. Even a small farmer can have large losses and real problem from heat stress.
There are fortunately several strategies that can be used to reduce the losses and significantly lessen or even eliminate the problem of heat stress entirely. Providing shade is a good place to start. A chicken coop built with access to the shade of several good trees is a definite advantage. A deciduous tree, which is one that looses its leaves seasonally, is the best choice because this allows more sunlight to reach the chicken coop when it needs it most in the winter months. Some trees are especially poultry friendly, including mulberry trees which provide extra nutrition from their falling fruits. Peach trees share a special symbiotic relationship with poultry. The poultry benefit from shade, insects and fallen fruits and the peach tree benefits from added nitrogen provided by manure, cultivation provided by the chickens scratching, and a significant reduction in pests like the peach borer. Other plants can also be used to provide shade for chickens. Grape vines, wisteria, trumpet vines or even annuals like pole beans will provide excellent shade for a chicken run. One thing to consider with vines however is that they not be grown so thickly that they interfere with air flow. Even a purchased shade device like shade cloth or even lattice or a discarded window shade can lower temperatures, just less attractively. With mobile coops you can also take advantage of the shade provided by other permanent structures. By parking my City Biddy Hen House on the north side of our garage, my hens have plenty of shade during the hot months.
Situating the poultry pen to take advantage of summer breezes will make a big difference in the comfort level of your animals. Keep grass and weeds mowed short for a distance around the poultry coop and pen. Tall plants can block the air flow to your birds. Take advantage of natural air flow in the coop as well. Building your coop with air inlets, that are well predator proofed, near the coop floor and an operable window or vents near the roof level will allow good air flow. Since heat rises the hottest air will escape out of the upper vents. This creates a vacuum of sorts and cooler air will be pulled in from the lower vents. Ventilation of this kind is even useful in the winter to help keep the coop dry without resulting in drafty conditions for your birds.
Proper bedding can be helpful for keeping your birds comfortable and cool. Providing clean bedding inside and out during the summer months not only helps your birds fight parasites like lice and mites, it also is much cooler than deep litter, which may actually add to the heat of the hen house as it composts. Providing bedding, like bark or cedar mulch, in the outside pen can help in several ways. While cedar chips are not recommended inside of the coop because of the strong smell and fumes they exude, the cedar mulch when used outside, also helps to repel flies. The mulch which retains moisture longer after a rain shower, also keeps the dirt beneath it moister and cooler. Chickens enjoy scratching down through the mulch to the moist soil beneath looking for worms. Hot hens like nothing better than digging a nice hole and then having a dust bath in the cool soil. Providing a dust box full of garden soil with diatomaceous earth or a little wood ash in it, is another way to make your hens happy.
Feed your hens right when it is hot. Providing your hens with plenty of nutritious feed, including fresh greens will help with heat stress. Juicy treats like spoiled fruit or melon, squishy old tomatoes and even small amounts of sour milk will be relished. Greens and juicy treats will also keep dehydration at bay and stimulate appetites when it is just too hot to eat.
Last and most important in fighting heat stress is water. Your poultry should never be without plenty of fresh water, but during times of extreme temperatures that rule is more important than ever. Change the water daily to keep it especially fresh and cool. This practice also helps prevent mosquito larvae from developing and causing problems for you as well as possibly spreading diseases like West Nile Virus and Avian Flu. Some people freeze large ice cubes to place in the water to keep it extra cool. Provide multiple sources for water as well. If a lone fount develops a leak or gets knocked over your birds could be without water and during times of heat this could prove fatal. Water can be used to cool your birds in other ways besides drinking. Some people like to freeze water inside of milk jugs or pop bottles. These bottles are then placed around the pen to act like localized air coolers. This technique is often used with rabbits as well. Another method to use water is through the use of misters. The misters are set up in one corner of the pen. This allows the hens to enter or exit the mist as they choose. Usually hens prefer to stay dry however, so this method does not always work. If your area has a dry heat using the mister to make an evaporative cooler can also work. Evaporative coolers or swamp coolers, work much like perspiration. The water is placed on an object and then as air moves around the object, whether naturally or by using a fan, the water evaporates cooling the air around it.
Happy, healthy chickens grow well, lay lots of eggs, and remain productive. Heat stresses your flock and can be fatal, so when hot summer weather takes over where you live take action! By using the right strategies you can ease or even eliminate heat stress in your chickens.