Unregulated Backyard Chickens Pose Health Risk, Study Says

March 12, 2018
Amanda Carrozza

Amanda Carrozza is a freelance writer and editor in New Jersey.

A UC Davis study is calling for more regulations regarding chickens being raised in urban and suburban settings.

Although not considered part of the poultry industry, chicken ownership among US households has been on an upward trajectory over the past decade. Some poultry fanatics have even gone so far as to declare that chickens are the new dog.

But researchers and health advocates are calling foul. The chief complaint: When it comes to chickens being raised in homes and backyards, local ordinances and laws are not addressing human and animal health adequately.

Most recently, a University of California, Davis study, published in the Journal of Community Health, is calling for more laws to mandate how chickens in nonfarm settings are cared for. The study’s primary author, Catherine Brinkley, PhD, said current laws for urban farming do not keep pace with those for commercial growers.


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“Ironically, as people seek to take control over the way their food is grown, most ordinances fail to ensure basic health and welfare for birds and humans,” she said.

Chickens in the Home

While it is difficult to pinpoint the exact number of Americans who currently raise chickens in urban and suburban environments, a US Department of Agriculture (USDA) survey of homeowners in 4 major US cities (Denver, Los Angeles Miami, New York City) found that 0.8% owned chickens in 2013. An additional 4% said they planned to own chickens in the next 5 years, and nearly 40% were in favor of allowing chickens in their communities and would not mind if their neighbors owned chickens.

But what are the health ramifications? According to the UC Davis study, “provisions governing animal slaughter and routine veterinary care are rare, presenting a concern for monitoring and intervening in public health crises.” Yet, while over half of the respondents in the USDA survey believed that chickens in urban areas will lead to more illnesses in humans, most believed that eggs from home-raised chickens are better for you than eggs purchased at a grocery store. In fact, only 10.5% of Denver respondents strongly agreed with the statement that chickens in urban areas will lead to more illnesses in humans.

The Centers for Disease Control and Prevention (CDC) begs to differ. In an October 2017 report from the Associated Press, the CDC confirmed that more than 1100 people that year had contracted Salmonella poisoning from chickens and ducks. Almost 250 were hospitalized and 1 person died—a rate that was 4 times higher than in 2015.

Inconsistent and Limited Regulations

UC Davis researchers focused their study on 100 municipalities in Colorado, the only state to compile public data for animal shelter surrenders and other statistics. According to the study, the most common guidelines for poultry regulations focused on housing design, placement, and gender. Ordinances pertaining to the sex of the birds varied greatly from town to town, with some municipalities banning roosters altogether and others permitting only 1 rooster per a certain number of hens, and others still with no laws on the subject.

Regulations were also lacking with regard to cleanliness, ventilation, and food and water requirements. Researchers found that ordinances governing the slaughter of backyard chickens occurred in only half of the municipalities in Colorado—and many were vague. Even with the seemingly slim decrees surrounding chicken ownership, Brinkley said, “more poultry ordinances have been passed or modified in Colorado in the last five years than in the previous 100.”

What’s Next?

Brinkley recommends that there be more laws that mandate vaccinations, manure management, and general animal welfare in urban and suburban settings similar to policies and regulations imposed on commercial chicken ranches.