“Extraneous” Lab Animals Mass Killed in U.S. Labs

Lab Rats Cropped

The coronavirus pandemic has changed many aspects of the way we live and work. 

A recent article in the journal Science has highlighted what some of these changes have meant for individuals that work in labs that conduct animal research—and the impact this is having on laboratory animals. 

Importantly, it reiterates NAVS’ view on animal experimentation and why animals should not be experimented on in the first place.  

The article highlights a disturbing reality—that universities are asking researchers to “think hard about the mice they actually need, to freeze the embryos of valuable or unique strains, and—in many cases—to cull the rest,” due to disruptions to research and the potential shortage of animal care that could result from issues related to the coronavirus.

This means that researchers are euthanizing lab animals—and in high numbers.  For rodents, that often means they are killed with carbon dioxide, and to verify their death, may also have their necks broken. 

These horrific procedures are happening all across the country. An immunology lab at the University of Pennsylvania euthanized more than 75% of their mice, a lab at Harvard killed hundreds of their mice, and other researchers are preparing for the possibility of killing 90% of their laboratory mice.

While right now this mass culling seems to be restricted to laboratory mice, many are concerned that it may extend to other lab animals as well.

Eric Hutchinson, director of research animal resources at Johns Hopkins University, said, “We have not and will not euthanize any animals just to conserve resources.  We’re just asking investigators to re-evaluate which animals they actually need.” 

But did researchers even “need” these animals in the first place?

Times like these highlight the cruelty and waste of animal experimentation and why it is important now, more than ever, that we move away from reliance on animal models in science and ensure that more is done to protect the lives of animals involved in research.

Help NAVS ensure that the treatment of lab animals as expendable research tools, and not as living, sentient beings, comes to an end.DONATE »


Grimm, D. “‘It’s heartbreaking.’ Labs are euthanizing thousands of mice in response to coronavirus pandemic,” Science, March 23, 2020.