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Updated: May 30, 2026
07:54
Field-Based Thermal Physiology Assay: Cold Shock Recovery under Ambient Conditions
Published on: March 9, 2021
Heat and moisture production by broilers during simulated cold weather transport.
J M Watts1, L J Graff, M L Strawford
1Department of Chemical and Biological Engineering, College of Engineering, University of Saskatchewan, Saskatoon, Canada. jon.watts@usask.ca
Poultry Science
|August 17, 2011
Summary
Broiler heat and moisture production (HP and MP) increase as temperatures drop during winter transport. Understanding these rates is crucial for managing broiler welfare in cold conditions.
Area of Science:
- Animal Science
- Agricultural Engineering
- Environmental Physiology
Background:
- Broiler welfare during winter transport is challenged by heat and moisture accumulation in vehicles.
- Accurate data on broiler heat production (HP) and moisture production (MP) are needed for effective environmental management.
- Previous research has not fully quantified HP and MP under a range of cold transport conditions.
Purpose of the Study:
- To determine the heat production (HP) and moisture production (MP) rates of broilers under simulated winter transport conditions.
- To investigate the effects of varying cold temperatures and packing densities on broiler HP and MP.
Main Methods:
- Broilers were placed in a transport drawer within an environmental chamber simulating cold outdoor temperatures (-8 to -18°C).
- Two packing densities (Condition A: 15 birds/drawer, ~27 kg/drawer; Condition B: 19-22 birds/drawer, ~50 kg/drawer) were tested.
- Air temperature and relative humidity were measured upstream and downstream of the bird compartment to calculate HP and MP.
Main Results:
- At +20°C, HP and MP rates were consistent with published values.
- HP and MP rates significantly increased with decreasing ambient temperatures for both packing densities.
- For example, at -15°C, Condition A HP reached 87.5 W/kg and MP reached 22.08 g/h/kg, while Condition B showed lower rates at -18°C (45.92 W/kg HP, 12.33 g/h/kg MP).
Conclusions:
- Broiler heat and moisture production increase substantially as temperatures decrease during simulated transport.
- Higher packing densities may influence HP and MP rates, requiring careful consideration for vehicle ventilation.
- These findings are essential for developing strategies to maintain optimal environmental conditions and ensure broiler welfare during winter transport.
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