WILMINGTON, Del. – One of Delaware's chicken companies says the coronavirus outbreak has hit their staffing levels so hard that they cannot keep up with production.

That means about 2 million chickens owned by Allen Harim Foods will be killed at the Delaware and Maryland farms where they were raised, but their meat will not make it to market, according to the Delmarva Poultry Industry.

That announcement caught the attention of People for the Ethical Treatment of Animals, more commonly known as PETA. The group is calling for Allen Harim to at least kill the chickens humanely.

"In addition to legal and veterinary requirements, common decency demands that you give these chickens – who have suffered day and night in severely crowded, ammonia-ridden sheds and to whom you owe your livelihood – the quickest, most painless and most humane death possible," PETA's Vice President of Evidence Analysis Dan Paden wrote in a letter to the company that was shared with the news media Monday.

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Reduced staffing due to illness and concern

Allen Harim officials have not responded to repeated requests for information about how they're handling the coronavirus outbreak, or about their need to reduce flock numbers.

"The impact of COVID-19 on the U.S. chicken industry is becoming more apparent as the disease continues to spread throughout the United States," said Delaware Poultry Industry Executive Director Holly Porter. That includes Delaware and the Eastern Shore of Maryland and Virginia, an area also known as Delmarva, where processing plants are seeing reduced staffing due to illness and absences from those concerned about COVID-19, she said.

Only one Delmarva poultry company has announced needing to turn to a last resort of "depopulating flocks" due to COVID-19, Porter said.

A letter first shared online by Delaware radio host Dan Gaffney outlines the company's need to reduce the number of chickens it was growing due to a "downward trend" in attendance. A local grower who received the same letter told the same to The Delaware News Journal, part of the USA TODAY Network.

The April 8 letter signed by Allen Harim's Director of Live Operations Michele Minton estimates attendance was at 50%, meaning the company is unable to "harvest the amount of birds daily or weekly to maintain target weights and ages."

Companies like Allen Harim enter into contracts with individual farmers to grow the chickens they slaughter and process.

Generally, the companies supply the chicks and food, while the farmers supply the housing and care. Once the birds are big enough, they are sent to processing plants like the one Allen Harim operates to be slaughtered and processed into meat products, such as packaged chicken wings.

Minton's letter states that the company will begin "depopulating flocks in the field" on April 10, and that the company will reach out to farmers with more information and instructions if their flock is chosen.

The letter does not explain how flocks will be depopulated – an industry term for killed without being sent to market – but Porter said in an emailed statement that "approved, humane methods – the same methods approved for depopulation in cases of infectious avian disease" will be used.

"The methods used are accepted by the American Veterinary Medical Association and all state and local guidelines," she said in the email.

Delaware Poultry Industry and Minton's letter say farmers whose flocks are "depopulated" will be compensated for their losses.

Commercially grown chickens grow big fast – with some poultry houses built to raise flocks of 20,000 birds or more. On average, those chickens are ready for slaughter by the time they're 10 weeks old, or sooner.

Minton said in her letter that the company has slowed down setting and hatching eggs when staffing shortages due to the coronavirus began. But those impacts won't take effect for a few more weeks, and depopulation is needed to deal with too many chickens for the numbers of plant workers available.

Officials with Mountaire Farms and Perdue Foods did confirm positive cases of the coronavirus among employees, and said they were checking temperatures and tracing contacts to try to keep the virus from spreading among employees.

Perdue confirmed in late March that two employees at the company's processing plant in Milford, Delaware, had tested positive. A few days later, Mountaire Farms confirmed that one employee at its Selbyville plant tested positive for COVID-19.

Perdue spokeswoman Diana Souder said "we have had a limited number of cases in our facilities" and that the company has decided to no longer specify when individual cases occur "out of respect for our associates’ privacy under applicable confidentiality guidelines." She confirmed that Perdue does not have plans to depopulate flocks in the near future.

Mountaire Farms also has no current plans to depopulate, said company spokeswoman Catherine Bassett.

Contact reporter Maddy Lauria mlauria@delawareonline.com or on Twitter @MaddyinMilford.

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