Big 'MAC' helps Alberta producers handle spent hensDate posted: March 28, 2005
From battling potential extremes such as avian influenza to helping producers keep costs down, Alberta's new system for spent hen euthanasia is heralded as a breakthrough technology for the poultry industry.
In Alberta, the province's approximately 170 registered egg producing farms result in roughly 1.6 million spent hens annually, raising logistical, cost and animal welfare challenges.
But thanks to an innovative on-farm euthanasia system developed with research, industry and producer support, Alberta now has a tailor-made tool for meeting all those challenges.
The system, a Modified Atmosphere Chamber (MAC) designed by Alberta Agriculture, Food and Rural Development (AAFRD), can euthanize large numbers of birds rapidly and painlessly, using carbon dioxide. The structure is a six-foot wide by four-foot high and four-foot deep bin that can hold roughly 650 birds.
Based on trials at commercial operations, a two-bin system using around 20 people to constantly load and unload the bins can handle 30,000 birds in an eight to 10 hour day. Hens are unconscious within seven to 15 seconds of being in the chamber and dead within 30 to 60 seconds.
Susan Gal, General Manager of the Alberta Egg Producers, discusses the process and thinking behind the system's development, and how it will benefit the industry.
Q: Recap for us the issue of handling spent hens and why Alberta Egg Producers decided to support a new system.
A: Laying hens are considered "spent" at the end of their laying cycle, typically after 52 weeks in production. Up until about five years ago, roughly half of our annual spent hen flock in Alberta was transported alive to a federally inspected meat processing facility.
However, this was not an ideal situation, because spent hens are frail at the end of their lay cycle, and transportation can be stressful. Our board began thinking, at least 10 years ago, that ultimately on-farm euthanasia would be the best route to go. As a result, we set our goal to have 100 percent of our birds killed on farm.
Q: What approaches were investigated?
A: Our first approach was to work with Northern Alberta Processors (NAP), the main processor for our birds. What we were looking for a system where producers could use a tool for on-farm euthanasia, then have the processor take away the birds for rendering.
As a result, NAP came up with an electrical stunner. At first, they provided this tool and shipping service free at that time, because the value they were getting for the rendered birds was enough to cover their trip out, the utilization of the machine and the transport of the birds.
But after a while the markets for the products of rendering began to decline. As a result, NAP started charging for the freight portion of picking up the spent hens. With this added cost to producers, we started to see movement away from using the NAP machine. We also started to support more testing with the electrical stunner, and we found that because the birds are much better feather-covered at the end of lay, that the kill rate of that machine was starting to decline to an unacceptable level. That got us looking for other alternatives.
Q: What ultimately stood-out as the best solution?
A: There was another system developed at the University of Alberta called a MAC cart, which stands for Modified Atmosphere Chamber cart. That work was done by Dr. John Feddes and Dr. Martin Zuidhof, even prior to the time we began to work with NAP.The machine worked, but it was small scale. For a commercial producer to use that machine
would take them two or three days to take out their birds. That was a problem because time is critical for our producers - they need to get their barns empty, clean and disinfect and rest the facility for seven days before they repopulate. Obviously, the quicker producers can get those birds out, the better off they are.
However, we learned about another machine developed by Saskatoon Processing, which is an affiliate of NAP, which was basically a bigger MAC chamber. Saskatoon Processing brought a couple of those out for us to test, and it really did work well. We killed about 13,000 birds in two hours using two MAC chambers.
Q: Why not just go with that system?
A: What we didn't really like was the way the heat exchanger was working. It was relatively open and could potentially be dangerous to the people who were operating it.
And as well, the machines were designed to be handled by a big dump truck - the idea was to pick the bin up and unload the birds into the truck. Because of our colony producers, we wanted something that worked on a front-end loader, so producers could handle these units themselves and share them among the producers in the area.Engineer Darryl Slingerland and colleagues at Alberta Agriculture, Food and Rural
Development's AgTech Centre in Lethbridge took all of our information into consideration and built a new unit from scratch. That's what we have today.
Q: What are the key advantages to the new system?
A: The short answer is we got what we wanted: a system that is very humane, achieves quick and painless 100 percent kill, and one that producers can build and operate with minimal cost.
One of the main challenges was developing an improved heat exchange system that wasn't too costly. For example, we could have incorporated an oil and gas regulator that would work fine, but it would've doubled the cost of the unit.
What we ended up with was something Darryl Slingerland designed based on a modified hot water heater. In our initial tests in February, we ran the system at Willabend Farm in Claresholm - it didn't freeze up and it worked very well.
Overall, this is a very good labour-saving machine - producers can typically save two to three days of work compared to using other systems.
The system also gives us peace of mind that we have a much-improved tool for dealing with potential crisis situations such as avian influenza. If we're ever in a situation that requires large-scale reduction of our bird population, we can use this system to ensure that is accomplished in a humane manner.
Right now, we continue to work with AAFRD to develop and provide information / plans for the machine, to allow producers to build these units on their own farms. We expect we'll have many of these units in operation over the next couple years.
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