Dealing with heat stress in poultry

What is heat stress?

Heat stress can be defined as a condition caused by high temperatures especially when combined with high relative humidity and low air speed. It occurs because the birds’ core body temperature increases to fatal temperatures because of poor heat loss and limited coping means.

What are the immediate signs of heat stress in poultry?

• Panting and laboured breathing.
• Pale combs and wattles.
• Birds lifting wings away from the body, and squatting closer to the ground.
• Lethargy, a general lack of energy and enthusiasm.
• Seizures, convulsions and staggering.
• Thirst increases due to the huge loss of electrolytes, wet droppings/ diarrhoea may also be more visible.

What effect does heat stress have on poultry?

Heat stress in poultry can be a serious threat to the birds overall productivity. The following resultant effects may be felt;

• A drop in production and in extreme cases an increase in mortality rates in a flock.
• Reduced growth rates, because the birds eat less.
• Reduced egg production and reduced fertility due to less mating in breeding flocks.
• Reduced egg quality – smaller shells may be noticed as well as thinner shells.
• Reduced hatchability

What can be done to minimize the effects of heat stress in poultry?

• Providing the correct nutrient levels and using more digestible ingredients, digestibility can also be improved by making sure birds are being fed the appropriate feed particle size, this way they spend less energy digesting.
• Provide cool, clean, low salt water.
• Ensure that feed is made available during the coolest part of the day, remove feed from the birds by deliberately lifting the feeding system 6 hours before the afternoon peak temperature, once the peak temperature is over, feed may be reintroduced. Removing the feeders also removes a potential barrier to air movement and reduces the birds’ heat output due to feed metabolism.
• Leave the birds alone during the hottest part of the day, don’t let children, dogs and other pets disturb them, this in turn keeps them calm.
• Stick to correct stocking densities as recommended by a technician, reduce body heat by putting fewer birds in each house while bearing in mind not to understock.
• Add electrolytes to water, electrolytes help balance the electrolytes in the bird and encourage them to drink more water.
• Provide protection from the sun especially for free-range poultry.
• Well ventilated and comfortable environments for the birds must be ensured, a misting/ fogging system can be installed in naturally ventilated spaces.
• Walk the birds gently but not in a disturbing manner, to encourage air circulation around the birds and stimulate water consumption.

This is where we will be ending our discussion for today. Remember to share your comments, views and opinions.