How do you measure a chicken鈥檚 happiness? Is it in the way it runs for food? How much time it spends preening?

To size up what might make chickens happy in their brief lives, researchers at the University of Guelph in Ontario, Canada, are putting 16 breeds through physical fitness and behavioural tests. They鈥檙e watching how well birds scramble over a barrier for food, how skittish they seem and whether they play with a fake worm.

Chickens can鈥檛 say how they feel, but playing with a fake worm may be a sign of happiness.

鈥淲e have to infer when an animal is happy or content or experiencing pleasure based on their behaviour,鈥� said Stephanie Torrey, one of the researchers.

In recent years, the animal welfare world has moved beyond looking at how to minimize suffering to exploring whether animals can also enjoy their lives, Torrey said.

Such measures may be considered irrelevant by companies but underscore a broader lack of consensus around the welfare of chickens, which are sometimes slaughtered as soon as five weeks after hatching.

Animal welfare advocates say cruelty begins with birds that have been bred to have breasts so big they can barely walk. They say today鈥檚 chickens are genetic monstrosities crippled by pain and that the industry needs to switch breeds.

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Many in the industry say there鈥檚 no problem and that chickens may not move around a lot because they鈥檙e sedentary. Even if they were to agree to change breeds, it鈥檚 not clear what the alternatives should look like.

The two sides disagree about the cause and frequency of health issues among broilers chickens. Tyson and Sanderson Farms, for example, acknowledge that chicken breasts have ballooned over the years, but they say they鈥檙e not seeing widespread problems as a result.

鈥淚f they can鈥檛 move and get to the feed trough, they鈥檙e not going to survive,鈥� said Mike Cockrell, chief financial officer for Sanderson Farms.

John Glisson of the U.S. Poultry and Egg Association says broiler chickens are 鈥渃ouch potatoes鈥� and that some people may mistake the birds鈥� laziness for a medical issue. He said trying to assess welfare is tricky beyond established industry measures, like whether a chicken dies from disease before it鈥檚 slaughtered.

The industry says changing breeds is unnecessary, and that switching to broiler chickens that don鈥檛 grow as big or as fast would mean using up more water and other resources. Chicken prices at the supermarket would be higher too.

Still, animal welfare is becoming a bigger public relations concern, and companies say they鈥檙e always looking for ways to take better care of their chickens.

Tyson recently ran a trial that let chickens pick from pens with varying levels of light to determine which they prefer. Perdue is testing giving its conventional birds as much light and space as its organic birds, which are the same breed.

The Humane Society of the United States says stepping up living conditions helps, but it believes the bigger problem is breeding that has resulted in disfigured chickens. It says chickens have been genetically manipulated to have massive breasts their legs cannot support.

鈥淚t is crazy for anyone to have to remind the industry that birds naturally walk,鈥� said Josh Balk, the Humane Society鈥檚 vice-president of farm animal protection.

Balk said the study in Canada will provide important information on what type of chickens might suffer less.

University of Guelph researchers are also tracking chicken traits like weight, growth rate and meat quality they hope will be useful to the industry. Aviagen and Tyson-owned Cobb, which supply breeds to chicken producers, are providing birds for the study, including breeds that are widely used.

The companies say they already track health and welfare, but that they鈥檙e interested in the research.

The Guelph study is being funded by the Global Animal Partnership, which certifies corporate animal welfare standards. In 2016, it launched a campaign to get companies to switch to 鈥渟lower growing鈥� breeds. Since then, it has acknowledged that chicken welfare is more complicated than just growth rate.

It鈥檚 now pushing for a 鈥渂etter鈥� chicken, and hopes the study will help define what that entails.

Only a small percentage of chickens in the U.S. are GAP-certified, and spelling out new requirements for breeds risks making certification even rarer.

Anne Malleau, the group鈥檚 executive director, notes some of the researchers鈥� tests may seem far out. But she said providing 鈥渆nrichments鈥� 鈥� such as places where chickens can rest or perch 鈥� was also seen as a fringe idea before becoming more accepted.

GAP was founded a decade ago with funding from Whole Foods, which still pays Malleau鈥檚 and another staffer鈥檚 salaries.

Back in Guelph, researchers note that chicken traits can make for marketable imagery. That includes behaviours like their willingness to engage with a fake worm 鈥� which they note may be misinterpreted as 鈥減laying鈥� and happiness.

鈥淭he jury鈥檚 still out whether domestic chickens, with their comparatively smaller brains, have the capacity to play,鈥� Torrey said.

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The Associated Press Health & Science Department receives support from the Howard Hughes Medical Institute鈥檚 Department of Science Education. The AP is solely responsible for all content.

Candice Choi, The Associated Press

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