Michigan Rep. Mike Bishop wants an investigation into the Department of Agriculture’s “secretive and problematic” experiments that have reportedly led to the deaths of hundreds of kittens.

Bishop sent a letter on Tuesday to Secretary Sonny Perdue about the cats’ treatment in the experiments, WTOP reported.

The Michigan Republican’s letter said his office researched a project called “Toxoplasmosis in Cats” being conducted in Beltsville, Maryland.

“I’m shocked and disturbed that for decades the USDA — the very organization charged with enforcing animal welfare laws — has been unnecessarily killing hundreds of kittens in expensive and inefficient lab experiments,” his letter read.

Bishop’s letter described how cats were bred and then fed meat infected with toxoplasma so their feces could be collected to harvest parasites, after which the cats would be killed and their remains destroyed by incineration.

“Any government research program like this one that’s been funded since the Nixon administration needs to be put under the microscope, especially when it involves using kittens as disposable test tubes in harmful tests that most taxpayers oppose,” Bishop said in a statement.

Kim Kaplan of the USDA responded in an email to WTOP that using cats was “essential to the success of this critical research” and that “the estimate of 100 cats used in the research … is a serious overestimation.”

Kaplan also said the cats could not be adopted out because they could pose a risk to adoptive families.

“Women newly infected with toxoplasma during pregnancy and anyone with a compromised immune system should be aware that toxoplasmosis can have severe consequences,” Kaplan said.

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