The Salmonella Shuffle by Katharine Mieszkowski and Julia B. Chan

Chicks arrive at Gunthorp Farms in northern Indiana when they're just a day old – but they already may have salmonella. Here in the brooder barn, the birds get a vaccine against the bacteria.

NOTE: Gunthrop Farms chickens haven’t been linked to any human illnesses from salmonella, but it’s an ongoing battle to keep the bacteria in check.

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When they're a few weeks old, the chickens go to live and eat on the pasture. It looks picturesque, but out in the open is another place where they can get salmonella from wild birds, rodents or each other.

Credit: Darren Hauck for Reveal

Inside the Gunthorps’ very small processing plant, chickens await slaughter. Before the birds enter this facility, all steps the Gunthorps have taken to control salmonella are voluntary. But in the plant, federal regulation finally kicks in. This means that certain sanitary standards, which an inspector oversees, need to be upheld.

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In the kill room, chickens are shackled together before they’re killed. Salmonella, which lives in the chickens’ gut, can get spread onto the birds’ feet, feathers or skin from their feces. In the U.S., about 25 percent of chicken pieces sold in grocery stores are contaminated.

Credit: Darren Hauck for Reveal

Blood drains from a bird that’s been stunned and had its throat cut. As the carcasses go through processing, salmonella may spread from bird to bird.

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Dead chickens go into the scalder and then the plucker to have their feathers removed. As you can see, the birds are mixed together, making it easy for salmonella to spread.

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When the chickens are gutted, there’s a real danger of contaminating the meat and skin with fecal matter, spreading salmonella. The necks are cut off because the Gunthorps have found that leaving the neck attached increases the risk of contamination.

Credit: Darren Hauck for Reveal

The processed birds end up in a antimicrobial wash, a solution used to kill lingering bacteria left on the chicken – inside and out. Federal testing occurs after this step. To meet the standard, 7.5 percent or less of the poultry examined can test positive for salmonella.

Credit: Darren Hauck for Reveal