Stiewert, Austin Michael (2020-07). STRESS AND EFFICACY OF GASEOUS EUTHANASIA UNDER VARIOUS LED LIGHTING FOR NEONATAL CHICKS AND DUCKLINGS AND COMPARING ON-FARM EUTHANASIA METHODS FOR DUCKS AND TURKEYS. Master's Thesis.
Euthanasia in poultry is a major welfare concern and optimizing the methods on-farm, at the hatchery and at the processing plant is paramount. Lighting greatly affects poultry behavior and welfare therefore the lighting conditions during euthanasia may be one method to improve welfare. Furthermore, on farm euthanasia can often be difficult so finding the most effective method which is also the most user friendly is also important for optimal welfare. The first experiment aimed to investigate the use of different lighting conditions during the use of CO2 and N2 during neonatal poultry euthanasia. The second experiment investigated the use of different colors of light during stunning of broiler chickens and their effect on stress hormones. The third experiment consisted of on-farm euthanasia of turkeys both 8 weeks and 12 weeks of age using various captive bolt devices and cervical dislocation methods. The final experiment compared the efficacy of an experimental crossbow with a known effective captive bolt Zephyr-EXL on market age Pekin ducks. The first experiment showed carbon dioxide combined with the absence of light was the optimum euthanasia condition for neonates. Experiment two, demonstrated that green lighting had the lowest CORT concentration for both broiler chickens and Pekin ducks and is considered effective in reducing stress on poultry prior to slaughter. Experiment 3 and 4 both demonstrated that while all euthanasia methods resulted in successful euthanasia, the captive bolt devices were more effective and easier to perform proper euthanasia. Furthermore, the experimental crossbow was indicated to be the best method overall. In conclusion, CO2 in conjunction with the absence of light is considered the most effective and humane method of neonatal euthanasia, while green light should be implemented during pre-slaughter. On-farm euthanasia showed captive bolt devices are more effective and humane than cervical dislocation methods. The Experimental Crossbow was similar to other captive bolts and should also be considered as an effective euthanasia device.