Heat Stress Prevention in Poultry

Small chick showing signs of heat stress with open beak breathing.

Technical Corner

Latest insights and information from our Technical Director

By Nigel Strain

Here in the UK and Europe summer has finally arrived, and whilst we all enjoy some nice, warm weather we must also be mindful of the challenges within our poultry houses’ environment. 

Small chick showing signs of heat stress with open beak breathing.

Record-breaking temperatures, as well as record-breaking production year on year, means that removing excess heat from our broilers is an increasing challenge.

Signs of heat stress

80% of the heat within a broiler house is produced by the birds themselves (metabolic heat) and birds have 3 methods of losing heat – conduction, convection, radiation. Once the body temperature climbs above the broilers’ normal range (40-42C) they will begin to show early signs of heat stress such as wing-spreading and slow panting and this will progress to faster panting as their body temperature increases further. If it reaches 45C and above, there is a high probability of death. It is therefore crucial that we manage to balance bodyheat production and bodyheat loss during periods of warm weather to protect the birds’ welfare and maintain performance.

Remove excess heat 

It can become difficult for a fully feathered broiler to lose enough of its body heat once the ambient temperature reaches above 27C and heat stress often affects broilers towards the end of the fourth week onwards when stocking density is at its peak making it challenging to remove excess heat trapped between the birds and litter. Carefully encouraging the birds to get up and move can help release this trapped heat.

Relative humidity

Relative humidity is also a key factor to consider along with temperature, as excess moisture in the air will mean the birds’ panting (evaporative cooling) will be ineffective in reducing their body temperature. Quite often, birds succumb to heat stress during the night, and the reason for this is that the RH is higher at night despite the cooler temperature.

The Heat Index is a useful tool – if the temperature in Fahrenheit and RH% adds up to 160 or more your birds will be suffering heat stress and will be in the danger zone.

Cooling equipment

Effective temperature is the key consideration, as with the right cooling equipment a bird can feel comfortable at high ambient temperature. For instance, a good tunnel ventilation system capable of providing at least 3 meters per second of airspeed consistently across a house of fully feathered birds will provide a great chilling effect of at least 6C and remove excess heat from the poultry house via rapid air exchange.   

Misting systems or cooling pads are also good options, especially in regions with low humidity, as they cool the incoming air which will drop the house temperature, but these can be challenging in humid conditions as they will cause an increase in RH% (around 5% per 1C of cooling).

Preparation is key

Being well prepared will help prevent heat stress issues – check your houses are well insulated, check that all ventilation equipment is working before they are needed, check the weather forecast at least daily, reduce the set temperature in the evening and at night to keep the birds cooler, helping them de-stress and catch up on consumption after a hot day (this will also help them to tolerate the heat of the following day). Adding electrolytes to the water system can also help during such stressful periods.  

I hope you all have a lovely summer and remember that the team here at OPTIfarm is always available to support you and your birds through it!  

Practical Future Farming at PIX

OPTIfarm Events

This month we are heading to the Gold Coast to discuss Practical Future Farming at the Poultry Information Exchange (PIX)

This year’s event will be held at the Gold Coast Convention and Exhibition Centre from Sunday, 15 to Tuesday, 17 May 2022.


One of the most diverse ranges of solutions available to farming today and in the future is that provided by technology and data. 

We all know that our industry is facing various degrees of challenges and ever-growing risks but the demand for healthy nutritious food on our tables does not waiver. 

Practical future farming will be about reducing the risks in your business to make your farming more predictable, more manageable, and more transparent. To achieve this, expect some investment in technology along the way and the likely need for some external services and support to achieve your goals.

Poultry Tech Support Routine

Technical Corner

Latest insights and information from our Technical Director

By Nigel Strain

 Today I have provided poultry tech support to clients across four continents, without the need to leave my home here in beautiful North Wales! 

My day started by providing ventilation support to a good client based in Sydney Australia, where they were having issues with their tunnel inlets (yes – it’s lovely and warm over there currently!) It is vital that tunnel ventilation is operating correctly when it’s needed, allowing it to provide the necessary cooling effect and prevent heat stress on the birds. 


Water reduction investigation

My second task of the day was to investigate the reason for a reduction in water consumption in a broiler house for our good client in Thailand. It’s always a concern when water consumption is off-trend and a sure sign that something is amiss either in the environment or the health status of the birds.

“Optifarm is a truly global business. We are proud to provide a cost-effective and time-efficient service and care to each of our clients all over the world.”

High levels of CO2

Next request was from our good client in Johannesburg South Africa who had issues with high carbon dioxide levels in their houses. In South Africa, it’s common to use coal furnaces to heat their poultry houses. It’s important to ensure adequate ventilation; minimum ventilation is key to removing toxic air and excess moisture from the house, providing the birds with good quality air.   

Overnight temperature variations 

Here in the UK we’ve recently experienced cold overnight temperatures and windy conditions. A good client asked for advice to prevent their houses getting cold overnight. Heating capacity is so important during the winter months, and this client has the advantage of gas heaters to support their biomass system. However, minimum ventilation shouldn’t be set too high and it’s worth considering increasing set temperature slightly in the evening when you know it’s going to be a particularly cold night.  

Understanding expectations

And there was still time in the afternoon to onboard a new client via a virtual meeting! Our onboarding process is key in understanding each client’s needs and expectations, which allows us to provide a great service from day one! 

Optifarm is a truly global business. We are proud to provide a cost-effective and time-efficient service and care to each of our clients all over the world. We take great responsibility for our carbon footprint and sustainability. Innovative technology, including artificial intelligence, allows our poultry technical support team to virtually globe trot, remotely supporting clients with their technical issues without any risk to biosecurity – a great advantage given the increased threat from avian influenza, viruses, and diseases.  

A little rumination

Our new world certainly brings challenges, but there are many good opportunities too. Whilst there’s absolutely a need to be face-to-face sometimes when conducting business, we can also take advantage of remote and virtual working, and not only during a pandemic! Sitting here at my comfortable home office, I’ve embraced my new way of working and the positive changes that it brings – fewer hours wasted in traffic jams, less time away from family and friends, not having to stress about delayed flights and missed connections! Positive change is good for the soul, good for the environment, good for the pocket!