Comparison of water-based foam and carbon dioxide gas emergency depopulation methods of turkeys

Recommended response strategies for outbreaks of avian influenza and other highly contagious poultry diseases include surveillance, quarantine, depopulation, disposal, and decontamination. The best methods of emergency mass depopulation should maximize human health and safety while minimizing disease spread and animal welfare concerns. The goal of this project was to evaluate the effectiveness of 2 mass depopulation methods on adult tom turkeys. The methods tested were carbon dioxide gassing and water-based foam. The time to unconsciousness, motion cessation, brain death, and altered terminal cardiac activity were recorded for each bird through the use of an electroencephalogram, accelerometer, and electrocardiogram. Critical times for physiological events were extracted from sensor data and compiled in a spreadsheet for statistical analysis. A statistically significant difference was observed in time to brain death, with water-based foam resulting in faster brain death (µ = 190 s) than CO 2 gas (µ = 242 s). Though not statistically significant, differences were found comparing the time to unconsciousness (foam: µ = 64 s; CO 2 gas: µ = 90 s), motion cessation (foam: µ = 182 s; CO 2 gas: µ = 153 s), and altered terminal cardiac activity (foam: µ = 208 s; CO 2 gas µ = 242 s) between foam and CO 2 depopulation treatments. The results of this study demonstrate that water-based foam can be used to effectively depopulate market size male turkeys.