It goes without saying, most poultry can have health issues with external temps that are very hot. Coupled with high humidity at the same time, it can be fatal if we do not give our birds ways to cope. Most of the management techniques are intuitive, like making sure they have cool water to drink and relief from the sun in the form of shade. Those remedies are widely discussed and I don't think need any further discussion in this article. I would like to focus on other ideas that I think are not widely discussed or thought of. For purposes of this article, I am offering these suggestions when temps are above 85 degrees and especially if humidity is high,
WHAT HEATS UP + WHAT COOLS DOWN
Physical activity and internal energy in the way of digestion can cause body temperatures to rise. In the winter, we encourage both these activities to bolster internal heat through digestion and stimulating circulation through exercise. During intense heat, we want to limit both of these. Poultry will naturally stand or sit quietly in the shade during hot weather. We should encourage them to relax and not stimulate them to move around. Free ranging should be limited or not allowed. Digging shallow pits in the earth in the shade for your flock to lay in can be very beneficial. The dirt will draw the heat from their bodies through the skin. Sometimes poultry will dig these holes themselves.
High temps are also the time to not feed your birds. Fasting is preferable, and feeding when temps are cooler in early morning or late evening is when a bird will naturally choose to eat during hot weather. Digestion will stimulate body temps no matter what kind of food it is. Fasting also has a calming effect. Lower protein levels will also be helpful as protein takes a lot of energy to digest. To compensate for the fasting periods, providing nutrient dense foods, along with fats when feeding resumes during cooler temps.
Feeding poultry ice or frozen foods is also a very temporary "fix" to reduce internal temps. Once ice is consumed, the body will quickly digest and raise the cold water to optimal body temps within minutes. This is for organ protection from the frozen water. If herbs and food are added to the ice, it will raise temps through digestion.
I have read using the herb mint as reducing body temps. I am all for using herbs, but this herb does not reduce body temps. The volatile oils in mint only give the sensation of coolness in the mouth and this is again from human experience. Birds not only do not have that many taste buds to appreciate this, but it does not actually lower body temps. It is a taste sensation and nothing more.OPEN VENTILATION
I house my birds in an "open air" wire covered pen. I highly recommend a run that is covered in hardware cloth, having a solid roof and predator proof. My flock naturally started to want to sleep out in the pen on hot nights (right?). They have since moved on to living there year round, but that is another article. This makes total sense and I think we need to maximize ventilation and consider this type of housing in the heat of summer. I think we need to rethink housing design to include way more than small ventilation openings and small windows.PH BALANCE
The PH balance in poultry can be challenged due to the depletion of vitamins and minerals and increased respiratory rates due to panting. Vitamin C is especially depleted with heat stress and this can weaken the immune system.
Water loss happens due to respiration with panting, but if water consumption continues, this should be manageable. During a long heat wave, you need to more rapidly refill waterers with cool water to keep the hydration levels up.
Online it seem to be generally recommended to add electrolytes for heat stress management. The only time I consider adding electrolytes for consumption is when really rapid or restricted water loss occurs, like when a bird is experiencing diarrhea with illness, or when chicks are without water during the shipping process. Electrolytes are often recommended for humans during hot weather because we can sweat profusely and can lose a lot water rapidly that way. Poultry don't sweat, so electrolyte replacement on this level is meaningless.
Comparable to the gut managing microflora, I think the body is best at managing the PH balance. I think it makes more sense to replenish lost minerals like potassium and magnesium. High vitamin content, especially Vitamin C can also help during hot weather. Heat stress can especially deplete Vitamin C and introducing it back can support the immune system and relieve stress through its alkalizing action in the gut.Herbs and foods high in vitamins and minerals and made into a tea or broth would be perfect in the drinking water. Your poultry will get the nutrition to help balance the PH and not heat the body with digestion.METHODS
• Provide clean drinking water. Cool water temp is preferable. Water filled foods like watermelon is OK.
• Provide a cool environmental areas shielded from the sun. Using bushes and trees are preferable to buildings as they will both emit cooling air from their own respiration as well as shade. Encourage restful activity.
• Maximize ventilation in housing. The more open wire areas to add more air movement, the better.
• Vitamin and mineral support, especially Vitamin C. Herbs that replace vitamins and minerals like dandelion, nettles, plantain, chickweed, violet leaves, lambs quarters, burdock leaves, leafy green vegetable, and some culinary spices are useful. Make a tea or broth with these plant materials instead of feeding whole and mix in the drinking water. Cut lemon slices can be added to the drinking water.
• Feed only in normal or cooler temperatures.
• Feed low protein foods.>
Sources: University of Florida IFAS Extention: Heat Stress Management in Broilers, http://edis.ifas.ufl.edu/vm019