Due to climate change, heat stress events are expected to become more frequent in broilers, with increased ambient temperatures adversely affecting broilers’ production, reproduction, growth performance, health and welfare. Reduced energy consumption for heating will be offset by increased energy use for cooling.
By 2050, global meat consumption is expected to increase to 455 million tonnes per year in response to the expected population growth and dietary shift towards higher protein food. Broiler production is a major part of the global meat market and the broiler industry is expected to meet approximately 40% of the increased universal demand for meat. Increasing and sustaining food production at this level will result in an increase in energy consumption.
Climate change impacts resources need for production
Conversely, there has been growing concern about the impact of climate change on broiler production given that it has been predicted that by the year 2100, the average temperature will increase by 2-6°C which constitutes a serious challenge to sustainable broiler production. Climate change will further influence the type and sophistication of broiler housing systems and alter the resource needs for broiler production. The economic and productive efficiencies of broilers are related to housing systems and climatic conditions. It is therefore essential to adapt broiler housing systems in line with the prevailing and envisaged climate change to minimise its adverse effects on the broiler industry.
Effects of climate change
Climate change is defined as the long-term deviations in climate patterns and temperature. The increase in global temperature, along with the desert encroachment and deforestation associated with climate change, will add to the burden of heat stress experienced, especially in tropical regions and during summer. Heat stress promotes behavioural, physiological and biochemical changes in broilers, resulting in economic losses. Additionally, it will lead to decreased water availability and an increase in the cooling energy required thereby potentially compromising broiler production, Âreproduction, growth performance, health and welfare.
Controlling the microclimate
Operating broiler houses at full capacity with bird flocks of uniform size is a common practice, one which enables more accurate control of the microclimate inside the barn and improves efficiency. Industrial broiler production involves controlling the indoor microclimate driven by the thermal flows occurring inside the broiler house and the requirements of the broilers throughout their growth stages.
Heating, ventilation and air conditioning systems are used to control the temperature in the broiler house. In winter, mechanical ventilation is used to circulate air and remove accumulated gases. In summer, ventilation and different forms of active cooling are used to maintain the inside temperature below a certain threshold. Evaporative cooling pads are the most common active cooling method used when temperatures exceed 30°C for periods of more than 2 to 3 hours.
