Research conducted by the University of Manitoba has shown, from an animal welfare perspective, nitrogen is a better alternative for mass euthanasia of swine than carbon dioxide.
The University of Manitoba in partnership with the Canadian Swine Health Board, Manitoba Pork Council and Manitoba Agriculture Food and Rural Initiatives is developing a mass mobile euthanasia system for swine and poultry to be used in the event of a foreign animal disease outbreak or some other animal health emergency.
The system uses nitrogen to reduce the level of oxygen to under two percent, sufficient to kill the pig.
Phase one of the project, which started about a year ago and is now complete, was to design and test a pilot system and phase two is to design a full sized system.
Dr. Qiang Zhang, a professor in Biosystems Engineering with the University of Manitoba, notes the current system uses carbon dioxide where as the new system uses nitrogen.
We actually compared CO2 with our new system.
We were looking at the two aspects, one is the animal welfare, the other one is the public perception.
Animal welfare is strictly looking from the animal’s point of view.
We actually use video tape to observe the behavior of the animals and with a panel of experts we actually score the welfare behavior.
Also we did the same thing with the public perception.
In quick summary, the nitrogen actually scored much better than the CO2 in terms of animal welfare but from the public perception point of view the two were pretty much equal.
Dr. Zhang notes because nitrogen is abundant in the atmosphere it can be extracted from the air on site where as CO2 would need to be transported to the site and, in the event of a large disease outbreak, there might not be enough CO2 available.