The Humane Society of the United States is pushing for the release of three dozen beagles that it says are being force-fed fungicides at a Michigan laboratory contracted by a division of DowDuPont.

The agency on Tuesday released the results of an undercover investigation it conducted last year at Charles River Laboratories in Mattawan, outside Kalamazoo. It said it documented nearly two dozen short- and long-term experiments that involved testing on dogs.

Some suffered for months and were killed at the end of the studies, according to the Humane Society.

The agency said the 36 beagles who survive until the designated end of the year-long test in July will be euthanized.

The Dow Twitter account released a statement saying it is trying to find alternatives to animal testing, and said the dog tests are required by Brazilian regulations.

"For months we have been urging Dow to end the unnecessary test and release the dogs to us," Kitty Block, president and CEO of the Humane Society of the United States and president of Humane Society International, said in a news release. "We have gone to considerable lengths to assist the company in doing so, but we simply cannot wait any longer; every single day these caged dogs are being poisoned and are one day closer to being killed."

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A petition on the Humane Society's website demanding the immediate release of the dogs had more than 60,000 supporters Tuesday afternoon.

In the Twitter statement, the company said it is committed to product safety and animal care. It said it tries to keep animal testing to a minimum and is working to find alternatives.

"Specifically, Corteva Agriscience, the Agriculture Division of DowDuPont, which includes Dow's former fungicide business, has been working closely with the Humane Society of the U.S. for many months to encourage Brazil's Agência Nacional de Vigilância Sanitária (ANVISA) to amend its animal test requirements for pesticides. Once Corteva is given certainty that the study is no longer required, they will stop the study immediately," @DowChemical tweeted Tuesday.

The undercover investigation ran from April to August, the Humane Society said.

In all, the Charles River lab performed tests on dogs for at least 25 companies during the investigation, according to the Humane Society.

"Among the beagles tested on, the Humane Society of the United States documented the horrible short life of one dog named Harvey who clearly sought attention by humans and was characterized by the laboratory staff as 'a good boy,'" the Humane Society said in the news release. "Harvey was being used to test the safety of two substances when poured into the chest cavity ..."

On its website, Charles River Laboratories said when the use of animals is required, "the research is highly regulated to ensure responsible, ethical and humane treatment." The company said animals are essential to understanding disease progression and drug safety.

The Humane Society said the scene inside Charles River Laboratories is a snapshot of what is happening at for-profit companies, government facilities and universities across the country.

“It is our obligation to tell the stories of the animals and move science, policy and corporate ethics into the 21st Century,” Block said.

Contact staff writer Ann Zaniewski at 313-222-6594 or azaniewski@freepress.com. Follow her on Twitter: @AnnZaniewski.

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