It’s not certain that a commitment by major grocery chains and restaurants to buy cage-free eggs will benefit hens.
The animal welfare science around enriched cages versus free-run egg production is murky because each system has pros and cons.
“There are really strong advantages for every single (egg production method), and there are disadvantages,” said Karen Schwean-Lardner, an assistant professor in animal science who studies poultry welfare at the University of Saskatchewan.
The grocery members of the Retail Council of Canada, including Walmart, Loblaw’s and Sobeys, announced in March that they intend to buy 100 percent cage-free eggs by the end of 2025. Tim Hortons, McDonald’s and many other restaurants have made similar commitments.
Animal welfare groups have applauded the pledge, but Schwean-Lardner isn’t convinced the decision is based in science.
A University of California Davis study from a year ago supports Schwean-Lardner’s position. Scientists there spent three years evaluating hen housing at a farm in the U.S. Midwest. They looked at conventional cages, free-run systems and enriched cages, in which birds have more space, perches and nesting boxes.
The scientists concluded that each method has “positive and negative impacts” on bird health, animal welfare, egg cost and worker health.
Schwean-Lardner also said caged hens are less likely to fight. About eight birds are typically kept together in a cage, which leads to a natural pecking order.
“They establish the top of that hierarchy, and the other birds learn their ranking,” said Schwean-Lardner.
Understanding who is dominant or passive reduces the likelihood of combat and prevents pecking and cannibalism.
In contrast, the California study suggested that bird mortality is twice as high in a free-run system. Open housing is more violent because it’s impossible to comprehend a pecking order when thousands of birds move freely throughout a barn.
“They don’t form the dominance hierarchy (arrangements) the same as the smaller groups,” Schwean-Lardner said.
“We often see more cannibalism and feather pecking in those systems than we do in the cage systems…. There is documented research where (producers) have lost 30 to 40 percent of their birds in a few days from cannibalism.”
Disease is also a problem in free-run systems because fecal matter is more abundant. In cages, fecal matter drops out the bottom and is removed.
Nonetheless, cages also have limitations, largely because birds cannot fly and move about freely in a cage.
“The welfare is never going to get any better (in the future) inside an enriched cage,” said Darren Vanstone, corporate engagement manager with World Animal Protection Canada, a global animal welfare organization with a regional office in Toronto.
“The cage-free systems … you can see where (welfare) would improve over time…. You see in well-managed cage-free systems, they tend to have better welfare.”
Skilled employees and better management might improve welfare in free run housing, but genetics, feed quality, group sizes, age and space can also affect behaviour.
“There are so many things that interact to cause cannibalism,” Schwean-Lardner said.
“It (management) plays a part, but if we had the best managers in the world, this would inevitably happen, because there are so many other factors.”
Canadian retailers and restaurants may be committed to cage-free eggs, but Egg Farmers of Canada has other plans.
Ninety percent of Canadian eggs are produced from conventionally caged hens. In February, the organization set a goal of reducing that number 50 percent by 2024, with the other 50 percent coming from enriched housing, free run or free range.
Vanstone is skeptical that Canadians will continue to buy eggs that come from a caged hen.
“In 10 years from now, consumers (will) not (accept) keeping animals in intensive confinement systems like cages,” he said.
“When consumers see an en-riched cage, they just see a cage. It’s really difficult to convince them (otherwise).”