Euthanizing animals was a huge part of my job. Labs don't usually use the reliable, expensive chemicals that vets use to put pets "to sleep," generally because the chemicals can affect postmortem laboratory results. So, in order to render animals into analyzable samples, scientists get somewhat inventive. One method for mice, referred to by the hair-raising euphemism "cervical dislocation," involves breaking the animal's neck, sometimes with your bare hands. For very young mice, you cut off the heads with scissors, or the aforementioned guillotines. Science!

Still, the most common method of euthanasia for many species, due to its cheapness, ease (for the human performing it), and speed, is suffocation with carbon dioxide. A lot of studies have examined whether the animals suffer during this -- the results are always inconclusive, making critics of the studies question the logic of endlessly killing animals with gas just to check if we can kill animals with gas.

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Spoiler: Yes.

Labs don't report how many animals they kill, so no accurate numbers are available. But based on the number of mice I put down on an average day (about 150 to 200), and the number of comparable labs in the country, I would estimate that U.S. labs kill upwards of 16 million mice per year (the Humane Society estimates 25 million). For scale, that's about 40 football fields packed tight with a layer of mouse corpses.

Jessica Addams
Or enough to lower the global happiness index a couple of points, if you prefer.

So why do we do this? Animals are "culled" because they are the wrong sex, are surplus to requirements, or don't have the right genome. Animals whose ID card is lost or damaged become useless for research because they cannot be identified; they are culled. Animals which have survived experiments cannot be used in another experiment because the first experiment may affect how they respond to the second -- these, too, are culled. Animals who show signs of stress may be culled "to put them out of their misery." If it's not financially feasible to treat an animal that gets a disease, then it's say hello to the guillotine.

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"This one can't tell a good knock-knock joke."
"Maybe he can get some pointers from God. Introduce them."

And, yes, sometimes death comes to animals for really stupid reasons. One time, one of my labs ordered some adult female rabbits and was surprised to find that one had given birth to a litter of baby bunnies while in transit. The researcher had no use for them (and had not applied for permission to have any extra bunnies), and the breeder could not take them back as they had been exposed to pathogens outside the breeding facility. So the veterinarian on duty euthanized them. He cried while doing so. Everyone in the room cried.

You might be asking, "Why not just give the non-diseased ones away as pets?" Well, many of them are copyrighted by the lab that bred them, with researchers signing agreements not to let any of them out of their control. Others are immunosuppressed or otherwise genetically damaged so badly that they couldn't survive outside a lab. Also, most of these are not popular pet species. Where could you possibly find enough homes for 30,000 mice? You would need 3,000 very big snakes.

So, many strains of mice and rats have been deliberately bred to "naturally" develop conditions very similar to human diseases, such as cancer or diabetes. To induce metabolic problems, you can also feed the mice special diets which make them fat or deficient in some mineral. Want to cure arthritis? First you must create it by injecting "adjuvant" (a material which causes inflammation) into a rat to make it arthritic:

Jessica Addams
We neither know or want to know how they go about studying erectile dysfunction.

Want to cure a terrible parasitic disease which affects humans? First you must deliberately infect mice with the parasite. In one lab I worked with, they did this by putting the mice in plastic test tubes, with their tails hanging out of the end of the tubes, immersed in water full of liver flukes.

Jessica Addams
If you made it this far, congratulations: Neither this article nor life in general has anything sadder than that picture in store for you.

The really scary stuff appears in research related to recovery from trauma. Rats don't drive cars or join the army (as far as we know), so to help human accident victims or injured soldiers, we must deliberately inflict similar damage on animals so we can try to cure it. For research into traumatic brain injury (TBI), for example, they use several methods to damage the brains of (sedated) rats, including shock waves generated by detonating crystals with lasers. (Science!) One lab I worked with used an air-driven shock tube, which placed rats in metal cylinders and then damaged specific parts of the brain with high-pressure gas.

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Those of you with older siblings may remember a dumber, fartier variation of this.

I don't want to sound like I'm totally against animal research. Research on animals has helped to improve research on humans. By giving scientists clues as to what might be going on in the human body, it focuses our efforts, speeds our learning, and reduces the need to experiment on people. For example, the discovery that (human-induced) chronic myeloid leukemia (CML) in (custom-bred) mice was caused by a certain protein allowed scientists to focus their research on the actions of that protein and produce a drug that helped to treat CML in humans. So while it's true that animal testing is often a horrific, nightmarishly cruel procedure, it also saves human lives, and a huge amount of human suffering in the long run.

Whether or not you're OK with that is a decision you'll have to make on your way to the pharmacy. But still ...

This is the way it works -- universities do not put pictures of happy smiling lab mice on the admissions brochures, and you have to know the labs are there to be able even to look for them. I was appalled to find out that several facilities where I'd gone to school and later worked had huge animal labs which I'd never seen or heard of when I was there.

Why is it like this? Because a whole lot of people don't like what they're doing, and would disrupt it if they could.

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After reading the above entry, you might now be one of them.

Now, let's give animal advocates their due: Nobody did a lot of "is this humane?" research until animal rights groups started demonstrating to the general public. But that doesn't mean the average protest is going to do any good. Animal rights groups protested a lab near mine once, and mine just responded by getting more paranoid than usual about activists. What this did was remove everyone's incentive to report problems with animal welfare. Everyone was scared that any employee who expressed concern for animal welfare could literally be a spy. Plus, the threat of animal rights extremists barging into a facility and wreaking havoc (releasing animals, removing ID cards to derail research) makes facilities put up more security, making it even more difficult for casually interested members of the public to find out what the hell's going on inside.

The real irony in this is that nearly everyone who works in an animal lab really does care about animals. The veterinarians and lab techs generally sign up because they love animals and want them to be happy. But when you're on the job, you keep quiet about your love of animals and any concerns you might have about their treatment for fear of being labeled an animal rights nut.

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"I don't think they like this food. Maybe we should switch to Purin- I MEAN FLAVORLESS STORE BRAND!! I'M NOT AN EXTREMIST!!"

If it sounds like it's easy to infiltrate a lab, that's because ...

We laugh at how movies show labs with young, hot scientists instead of the aged professionals qualified for research. However, a real lab staff can really be that young or even younger. Someone with a Ph.D. leads the project, but everyone else in the lab does not necessarily have a degree beyond high school, and they may be students as young as 18. Though they're not incompetent by any means, and they are in no way intentionally evil, they have no more skill or attention to detail than you can expect from someone of that age. This can produce some extremely erratic research.

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"Subject A died instantly whereas subject B developed telekinesis. Not the results I would've expected from a cough drop."

Part of it is due to the game of "telephone" that goes on in the lab: The Ph.D. in charge knows all the techniques and protocols and teaches them first to his lab assistants (generally full-time paid personnel who are primary helpers), then to the various students (graduate assistants working on their own Ph.Ds, as well as undergraduate students getting experience in a field they hope to enter). Sometimes the assistants teach the students. At every step in the chain, some information is lost, leading to people at the bottom of the chain ending up with incomplete or wrong info. And we're all human. So, horrifying errors occur.

omaha.com

A student in one of the labs I worked with had the job of anesthetizing chinchillas. He did not have much practice in injection techniques and injected the wriggling animals the wrong way. They developed infections or paralysis around the injection sites (which were on their legs), and some had to be put down. Another student was presented with six adult Canada geese to kill so that the lab could harvest the eyeballs (they were studying how geese see, to help them avoid getting sucked into jet engines). The geese were supposed to be euthanized chemically, but the student didn't know this and for some reason did not feel able to ask, so he used a guillotine to euthanize the first goose, which had about the result you'd expect. He repeated the procedure on another goose before someone else managed to contact the Ph.D. in charge and correct the error. And here "correct the error" means "make the student stop chopping the heads off of huge, thrashing birds."

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Which should've been obvious to anyone whose spent more than 30 seconds around geese.

I do not want to imply that these two labs -- or any of the labs with which I worked -- were specifically terrible, malicious, or evil. No one working in these places went to work each morning thinking, "Today I will mangle some defenseless animals!" The lab assistants and students honestly believed they were working to advance science and felt genuinely awful if one of the animals was sick, or injured, or had to be put down due to a mistake they'd made.

But here's the thing ...

You might think lab techs would have to be cold on a Cruella de Vil level to be able to experiment on pets, but if so, they don't start out that way. When one student in one of my labs first began doing research, she had just three pairs of mice. She named them: Mickey and Minnie, Donald and Daisy, Benny and Joon. She spent time in the lab with them, worried over them when they got sick (which they inevitably did), and tried to enrich their lives by giving them toys. She cried when she had to euthanize one. Soon, though, the mice did what mice do, and the number of mice in her care rose from six to 80. By this time, none of the mice had names or toys. She euthanized them in batches without a tear.

As the number of mice in your care grows still higher, you may feel no pangs at breeding and killing dozens of spare animals on the side for no reason. I knew another scientist, a Ph.D., who had an active colony of 500 mice even though he was doing no research. They kept reproducing, and the lab techs had to keep culling a couple dozen individuals every month because the researcher was not authorized to have more than 500 mice. But the researcher wanted to always have some mice available, just in case, and the colony kept grinding out babies.

Jessica Addams
Even if you never do a lick of research, having a literal rodent plague on hand can make for one hell of an April Fool's Day.

My own solution for this was to try from the very beginning not to emotionally invest in any of the animals, leaving any advocacy on their behalf for after I was gone from the labs. But I did manage a small rebellion: I filled out paperwork to (legitimately!) rescue a surplus rat that was completely healthy but due for euthanasia because she had been "forgotten" by the researchers and was now too old to be used. I took her home a day before the paperwork actually went through. I named her "Felony."

This article is my second rebellion. I am no longer employed by a lab and am a loyal servant of the Rat King, free to let people know that this kind of thing is going on. It's some pretty important stuff, and besides, I promised the rats I'd tell someone about them. Felony lived out the rest of her days with me. She never was particularly fond of people, but she had what I can only hope to be a fine time ignoring me and shredding little cardboard toilet paper tubes. You might find this vaguely reminiscent of Rise of the Planet of the Apes, only with a mouse instead of a chimpanzee. But that turned out fine, didn't it?

Jessica Addams does not claim to have any answers. Her hallucinations concerning animal welfare, in which you are welcome to share, are available at www.animalfeasance.com. Ryan Menezes has lived with rats but out of poverty, not choice. Now, he lives on Twitter.

For more insider perspectives, check out 5 Horrifying Truths About Being a Medical Doctor and 5 Things You Learn Escorting Women Into an Abortion Clinic.

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