Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens

Area of Science:

• Veterinary Science
• Animal Welfare
• Agricultural Engineering

Background:

• Highly contagious poultry diseases necessitate rapid emergency depopulation methods.
• Current depopulation techniques require evaluation for efficiency and welfare implications.

Purpose of the Study:

• To assess the efficacy of compressed air foam systems (CAFS) for mass emergency depopulation of caged layer hens.
• To compare CAFS with and without supplemental carbon dioxide (CO₂) gas.

Main Methods:

• Two experiments utilized randomized block designs to evaluate CAFS depopulation on commercial layer hens.
• Methods included CAFS, CAFS with CO₂ gas, and CO₂ gas alone.
• Physiological parameters like time to unconsciousness and motion cessation were recorded.

Main Results:

• CAFS, with or without CO₂, rapidly induced unconsciousness in layer hens.
• No statistically significant differences were found in time to brain death, cardiac activity changes, or motion cessation between CAFS and CO₂ treatments.
• Bird age did not significantly impact the time to motion cessation when using CAFS.

Conclusions:

• Both evaluated CAFS are capable of depopulating caged layers.
• Supplementing CAFS with CO₂ gas did not provide additional benefits for depopulation efficacy.