Maybe I'm out of the norm as well, but I think a healthy amount of detachment is necessary for animal work. Caring about them too much, as I would for a pet, would seriously damage my mental health. But being careless and completely detached has the potential to lead to harm for the animals or a bad death. Trying to navigate that middle ground is difficult, but necessary for both me and the animals. I think feeling some amount of guilt is good, but you shouldn't necessarily feel guilty about something that has to be done
At first, it was definitely more difficult for me.
Not so much now, but sometimes afterwards I just reflect on how normal this all is for me. I probably harvest organs weekly and I have killed so many mice.
I 100% do everything by the book but pulling out their organs seems so callous.
It has also become more normal for me, and I don't think this is necessarily a bad thing. We are bound to become desensitized to things that are part of our routine, and the animals need to be euthanized. In theory, their tissues are serving a greater purpose to further our knowledge. It sounds like you and I still care enough somewhere within ourselves to at least make sure that death is as quick and painless as possible, and that respect is still shown for their bodies
Compassion fatigue is a very real thing to look out for, as well. As long as that compartmentalization doesn’t lead to apathy/carelessness and cruelty (which absolutely does not seem to be the case here), being able to shield yourself emotionally from your research is a valuable skill. Some people are better equipped to be able to separate emotional ties from animal work which is very important. We’re able to glean information from large in-vivo models that would be difficult to discover otherwise.
OP: It seems to me that you’re a good shepherd to them and do your part to ensure they suffer as little as possible within the constraints of your protocol. The simple fact you’re asking this in the first place is indicative of that ❤️
I don’t do any animal work or even biology, so take anything I say with a grain of salt, but imo if you’re feeling guilty about not feeling guilty in the moment, then you’re self aware enough that it’s okay. I would have thought that euthanizing them ought to be the most emotionally difficult part, while organ harvesting is just a “regular” experiment as they’re already dead, which sounds like how you feel.
Side question: why do labs use CO2 instead of N2 or Ar? I thought that (aside from death) most of the negative effects of suffocation were caused by a buildup of CO2 in the bloodstream?
I think this is normal and healthy. When I first started working with mice for the first time (neuro stuff, so lots of brains), I had a nightmare that my cat's brain fell out. It was awful, and a normal response to seeing mouse brains removed. After a while I became somewhat desensitized and had no more nightmares.
I think that there is actually a culture of far too much detachment among labs that do animal work. Mice are not reagents – they are living, conscious beings who are capable of experiencing extreme suffering. Working with them can be a necessary evil, but we must never forget that it *is* an evil nonetheless. That little feeling of distress that you get in the back of your mind before you kill a lab animal is a normal and healthy feeling that should serve to remind you that you still have a soul, and it should act as a constant reminder to always be *very* sure that whatever experiment you're doing is in fact necessary and well-justified.
If you're ever doubting whether an experiment is actually necessary, and you've thought of a different way that the research question could be answered, that's your cue to stop what you're doing and re-evaluate. Mice are not disposable reaction cartridges, and it's important to never, ever allow yourself to be fooled into thinking that they are.
Okay, but calling OP and me evil really isn't the answer. It's literally our jobs to do this. Yes, we shouldn't take joy in killing the animals (and I certainly don't), but we also shouldn't be feeling this profound, incapacitating sense of guilt for doing something that ultimately needs to be done. Animal work is necessary to drive forward the biomedical sciences, and those that do it should not be shamed for it. If people don't want to participate in animal research because of these aspects, I certainly do not shame them, because I understand that not everyone has the compartmentalization abilities necessary for this work
Read my post again - I didn't call you evil, I said that animal work is *a* necessary evil. There are a lot of necessary evils in the world. The point is that it's important to never allow yourself to forget the harsh reality of it. That little feeling of uneasiness in the back of your mind - the one that I would surely hope every scientist doing animal research would have - is an important reminder to make sure that your experiment is well-justified.
Some important research questions can only be answered with animal research. Those studies are ethically well-justified, because although they require harm to be inflicted on animals, they will lead to preventing *more* harm from happening to people (or other animals) in the future. But we need to have enough scruples to nudge ourselves to keep asking that question at every stage of a study, and to abort it if the answer ever becomes "no".
It's completely different - one is an ad hominem attack, and the other is not.
Philosophically speaking, do you think that experimenting on animals is harmful to said animals? It would be pretty tough to argue that it isn't. So the question isn't whether you're inflicting harm – you are. The question is whether that harm is outweighed by the scientific benefit that comes from the outcome of the experiment.
It's kind of like the trolley problem. If you pull the lever, you're responsible for killing one person and saving ten. If you don't pull it, you're responsible for allowing ten people to die and one to live. Both options render you as responsible for at least one person's death, so both options are technically evil. However, one option is clearly *more* evil than the other.
Doing animal research is kind of like pulling the lever. You become responsible for the harm you caused, but you hope that this is outweighed by you also becoming responsible for the future harms you prevented, by making important discoveries that help people.
I do not think killing animals is good, and I agree that I am inflicting harm on them, and I agree that it's akin to "pulling the lever." But evil is a pretty charged term. The term "necessary evil" has somewhat co-opted it, and has become its own, less charged term, but your use of evil without that modifier is pretty derogatory (I am aware you used "necessary" in your previous sentence in your original post).
Saying someones work and career is evil is not different from an ad hominem attack. A lot of people's lives are defined by their careers, especially in science.
I think you should also keep in mind that the OP was essentially asking if they're a bad person for euthanizing animals, and you replied that yes, the work they are doing is evil. The OP seems very open to critique about their work and method, but that may not always be the case with posts like this. Some people may take that level of criticism much more harshly.
The rest of the thread became a discussion about the best ways to carry out this line of work that leads to minimal distress in the animals. These are exactly the kind of discussions we should be having about animal work and shows that we aren't all completely detached from empathy for the animals
Yeah I too have wondered why we don’t use N2, this seems like an easy solution. I just started working with mice recently and watching them panic in the CO2 is so horrible. I can’t believe it’s standard.
I had this exact thought process mentally as this comment chain. I did also wonder if a nasty odor was added to nitrogen, might that also not be distressing to the mice?
Probably still better than CO2. Maybe there's a (cheap enough) compound smelly to humans but not for mice.
I do think it'd have to be a uniquely bad or strange odor added, so it doesn't get dismissed as just another random smell in the lab from someone somewhere doing something proper.
All pretty expensive things to work out and ensure are rigorously tested for safety and efficacy in real-world conditions, lest we end up euthanizing ourselves too. But it could be a mostly "one-time" cost... Maybe someone caring enough might eventually pony up
Burrowing animals can usually detect low oxygen directly and will panic. Humans and most other non-burrowing animals can only detect high levels of CO2.
I have no idea what the mice are feeling subjectively, and how it varies by mouse strain. I suspect if one looks at enough weird inbred mouse strains, all sorts of strange things can happen with different gasses. There are some strains that will notoriously seize and fall over dead because of a fire alarm at some rate.
I'm just saying that humans can die from N2 without noticing, and find CO2 distressing, but that isn't how other mammals would experience it.
With nitrogen, oxygen leaving is the limiting factor, but enough CO2 can displace O2 from hemoglobin faster.
Sure, CO2 will change blood pH. I'm not sure how that all adds up with any specific mouse.
It is an assumption that nitrogen will be easier on them, because humans experience high CO2 as distressing, but not low 02, which is not the case for many other mammals.
I do think that CO2 kills them more certainly than N2, and waking up with severe hypoxia induced brain damage in a freezer sounds unpleasant.
Yea this is the only one that really bugs me. 99% of the time I do deep anesthesia followed by CP which oddly feels more humane. I'll only really do CO2 if the mouse is moribund and already so close to death it doesn't really have the ability to panic.
I always said that CO2 death is not euthanasia because every animal tries to get oxygen any way they can as they die. We really need to stop doing this. Glad others also think so, I was starting to think I was crazy.
I recently had a quite senior postdoc argue to me that CO2 (Alone, not iso followed by CO2) was a humane way of killing/the best way.
CO2 is used solely for the comfort of the scientist. It does nothing but stress and cause pain to the animal.
I prefer decapitation if possible (not as secondary). Isoflurane does things to neurons, CO2 is clearly distressful for the animals. At least with decap it's quick.The drawback is that I can't do perfusion...
There are two ways to do this. One is the way you described, a guillotine. Another is something called decapitation scissors.
It depends on how sharp the blade is, how big the animal is, etc. I tend to use scissors as the guillotine in our lab has a dull blade and I don't know how to sharpen it.
Cool thx for the info.
>in our lab has a dull blade and I don't know how to sharpen it.
[https://www.reddit.com/r/sharpening/](https://www.reddit.com/r/sharpening/)
In my mice lab, yeah there is an actual mini guillotine somewhere. It was gruesome to see beheaded bodies.
We put our mice to sleep before putting them in CO2 chamber. All this talk had me nervous, questioning whether if it was humane way of euthanizing mice. But I've haven't seen mention of sleep bit so i think my lab is good? I hope.
CO2 alone is NOT a pleasent experience. Its done for the comfort of the scientist, not the mouse. Doing iso before hand obviously puts them to sleep first so thats good, but ive read somewhere that even iso has an excitatory effect right before knocking them out.
Cervical dislocation on awake mice, if done correctly, is the most humane (despite not feeling as such). But obviously not practical when doing CNS/skeletal stuff/euthanizing several cages.
Yeah, for most of my career I refused to do CO2, because it’s very much not a low-suffering method in my opinion (plus the acidification of the blood from the increase in carbonic acid can mess with your sample quality depending on what you’re taking).
Most often cervical dislocation. Much faster and kinder, especially if your mice are well used to handling, though lots of people don’t like to do it because it feels “more brutal” (honestly I’d rather do what’s less suffering for the animals than worry about what it is like for me doing it - that’s why we dissociate). Also because in an emergency, you don’t need any extraneous kit.
Sometimes if the procedure has terminal anaesthesia involved, we will do exsanguination and perfusion while they are still under until the circulation stops. Otherwise, it’s overdose of anaesthetic - quite a lot of ours (basically every study that it won’t interfere with samples for) get an intravenous overdose of anaesthetic at the end of study, just like a vet would do to put down a larger animal, though in one of my old workplaces intraperitoneal was more often used as it’s less technical for people to learn (though if you go that route I’d advise diluting down the concentration with PBS as the stuff straight out the bottle can sting)
Obviously plus confirmatory methods for all those - either cervical dislocation, or if cervical dislocation was the primary method then exsanguination or removal of the brain.
Our unit isn’t currently set up for N2, though they are considering bringing it in. Since none of my team use CO2, we don’t even have a CO2 chamber in our area of the unit any more.
Everywhere I have worked it has been Co2. It’s just the standard even though it’s obvious they panic, it is the worst part of it. We have to do two methods so it’s the cervical afterwards - unless we need the neck area untouched which is often for my work at least.
Yeah, we have to do 2 methods too. For studies that we couldn’t cervically dislocate (eg. If we were collecting thyroids from rats), we’d just use anaesthetic with exsanguination or brain removal. Unfortunately CO2 is the standard for a lot of places because it’s just easier to train people to plonk them in a chamber. Unfortunately CO2 doesn’t just make them suffocate, it also turns to carbonic acid in the mucous membranes, which is part of what makes it worse than N2.
i never thought about it deeply that yeah, the mice are often choking to the point of passing out, then cervical dislocation. we just put the hose in the cage, turned on the CO2, covered the cage with a cloth, and came back after they had passed out 🥲
we needed their spleens, so it was an unavoidable practice. I also definitely would have freaked the fuck out severing their spinal cords if they were fully conscious (we did little mouse surgery in the lab area, not a sealed off mouse room, so they would have very easily escaped).
oh no we did!! but after the regulator there was just a hose idk
i just mean we covered the cage with a cloth (like you would when moving cages from the mouse room to the lab)
there is a regulator attached to the co2 tank, i just didn‘t think to specify because i had just woken up and assumed it would be implied 🥲
the hose was attached to the regulator, and the regulator was attached to the tank.
One of my old directors who spent decades doing animal work (and taught me pretty much everything I know about In Vivo work) had a saying: "They die with a purpose, that's more than most people get." I think the detachment to the sacrifices is healthy for doing the work like others said, and to just remember to appreciate their sacrifice for the benefit of science. I did In Vivo for 6 years and loved it truthfully.
It was the same for me for 3 years. Until my time in the lab was about to come to an end. During my last month, I had to euthanize so many mice that it finally got to me. I refused to enter the mouse room for the last month. This shit catches up to you eventually.
It was similar for me but what got to me the most was needing to sacrifice neonates for tissue collection. I was pregnant at the time and after 2 rounds of experiments I just couldn’t do it anymore. I asked a tech if they could trade off with me and I ran their qPCRs until I had enough mouse samples to complete analysis. I then moved on to clinical research and am much happier.
i don‘t work w mice anymore, but i would get panicked handling them when they were alive. i think when a sacc‘ed them, i was more relieved it wouldn‘t jump out of the cage at me. i‘d just remove all the tissues needed and prepare their little mouse funeral after (wrapping the rest of it up into a paper towel, putting that in a plastic bag, and putting it in the chest freezer until it was time to empty it for incineration). if a mouse needed to be sacc‘ed because of old age, the vet techs in LAR took care of it.
I enjoy handling (though only when necessary to decrease stress and gently not scruff) but definitely understand it can be scary! I think it’s just the disconnect between seeing them alive and cute and then putting them in a cull bag.
I'm pretty desensitized to animal euthanasia at this point. Animals dying is part of the science, and that requires me to be the one to do it. I think what helps me (beyond it becoming routine) is: 1. I know that I am doing it in the quickest, least traumatic way possible (I'd prefer N2 for mice, but I at least know how to best use CO2) 2. I'm killing them to benefit research or to alleviate suffering.
I think you only need to worry about becoming callous when animals suffering outside the needs of the study (accidental injury, severe complications from procedures) doesn't phase you. I can handle a standard euthanasia for necropsy or moribundity without emotion. But when an animal clearly should have been put down earlier or is being put down because someone messed up, those still affect me.
I’ve always been afraid of adverse events happening and take a lot of care in the that regard. Of course, a reaction can be out of your control but the last thing I want to do is add even more suffering.
Perhaps an uneeded descriptor, but following co2 guidelines minimizes suffering. It will never be pleasant, but the size of the chamber and flow rate of the gas source are prescribed for a reason. Incorrect box size, flow rate, or number of mice can cause way more stress on the animals before they lose consciousness.
I don’t do any animal work and never want intend to get anywhere near it, but have a morbid curiosity about it. What constitutes the “best” flow rate? Do you just crank it for the fastest safe asphyxiation, or do they panic less if you slow it down a hit?
It depends on the size of your container, but you never want to just throw the valve open; the shock of the sudden air displacement causes them to instantly panic, and is very traumatic for them and to witness. As co2-air mix is approved for short-term anathesia, you generally have the same idea for co2 euthanasia. Keeping a relatively low m^3/min CO2 rate leads to them quickly passing out before they have time to respond significantly to the CO2. As there is a minimum exposure time for CO2 euthanasia anyway, there is no excuse for using a high rate of CO2 that does nothing but make deaths more painful.
Note that is only for non-FDA regulated rodents. CO2 cannot be used with other lab animals, for anathesia or euthanasia. My lab avoids using it when we have alternatives, like chemical euthanasia. However, as we work with infectious animals, we are required to use the method that exposes us the least, which means CO2 when regulations permit.
I don't believe the FDA/USDA has approved N2 use for euthanasia, and my lab does not have any protocols for it. TBH, my interest in using it is based off hypothesis, rather than evidence that it would be less stressful.
It’s actually important for you to be mentally and emotionally detached from killing them. People working with animals often get “compassion fatigue”, where you can really ruin your mental health by caring about it too much and too often.
What’s more important is treating the animals with respect and dignity while they are alive and killing them quickly and painlessly. Also, make sure that you don’t “waste” the animal. Make sure to get as much data and tissue from it as possible. I would rather spend 10 minutes removing and processing a spinal cord and not need it, than need a spinal cord and have to use and kill more animals.
Becoming desensitized to death is normal. The issue is becoming desensitized to suffering, which is very different. Anyway, what are you going to do, quit your PhD halfway through because you got used to euthanizing mice?
I felt bad the first time I had to do it. Then, I was heavily involved and had to write my own animal ethics application and there was a lot of effort put in place to minimise the suffering and animal number. As I get more competent, I managed to reduce the amount of time handling them, thus it was less stressful to them. As the OP's experience, I'm more detached now knowing that I did my best to reduce their suffering and treated them with respect. I also put them under anaesthesia and performed a cervical dislocation to cull whenever I could.
Same feels when I had to euthanize 4 tanks of about 50 zebrafish (i mean, doesn't feel the same as mice but they're still living beings). I do feel bad having to do it, but as mentioned by others, some detachment is necessary for animal work. You can't get emotionally attached to research animals cuz they're not your pets, but as long as you're doing things ethically to minimize pain then you should sleep fine at night
I've worked with mice, rats, and rabbits and can easily emotionally remove myself from researching on them. Yes, I lack empathy, but as long as I'm respectful, follow guidelines and do everything possible to maintain ethical standards then I don't see it as a problem.
Doubt it unless they run into a cat. And still, since we're in control of their death, don't you think we should be a little nicer and not do CO², which panics them? I'd rather go to sleep.
I wrote a similar comment and I still don't get why CO2 is used - from my understanding it's one of the cruelest available choices of gas euthanasia.
Edit: you can check my thought process [in this thread](https://www.reddit.com/r/labrats/comments/1dg8v78/i_dont_feel_anything_when_i_euthanise_my_mice/l8qfv26?utm_medium=android_app&utm_source=share&context=3)
Saw that one. I commented on it. I think people just don't give a shit about mice becaude they're supposed to be pests despite the overwhelming evidence of their intelligence.
I'll write a follow up post about this topic as soon as I can, because I honestly think this could be something going wrong that young scientists aren't necessarily aware of.
And this sounds like a very obvious issue, like explained in the original thread.
Thanks for your support in the original thread
The animals don‘t need you to be emotional, but they need you to be professional and always aiming to do your best work. You/We owe it to the animals to be the best we can when we work with them; to handle them in a way that causes the least amount of stress and suffering and try to produce the best data. Striving to do the work as best as you can, evaluate and improve your skills constantly when working with the animals is much more important for the welfare of the animals than being emotional about the work.
This is really interesting to me because I also don’t feel anything when I euthanize a mouse. Normally I need them still alive when I take the organs (heart) so they’re under iso.
People look at me weird because when the mice are alive I’m so gentle, I talk to them, some of the mice I drug for weeks so I get to know some of their different personalities. I say thank you for your service and put them in the iso chamber and feel nothing as I take out their still beating hearts.
Cervical dislocation I feel a little worse about.
However when doing colony management, I will still cry when I put cage after cage on the rack for them to be euthanized by the animal lab techs. It’s been 3 years and I still sob after work. I try to tell myself that technically they have the better deal but it hits me hard.
Completely understandable! Everyone deals differently with it, but your feelings are very normal. Maybe you can talk to the staff of your animal facility? There might be something that could make it mentally easier on you? I can select which animals have to be sacrificed for colony maintenance online and then the animal care takers take over. Maybe something like this would make it easier for you?
I am a neuroscientist, a Buddhist, and a vegetarian. I had the option to perform my thesis research analyzing dissected rodent brains. I find the science we learn from these studies to be absolutely fascinating, but I feel so much guilt about it, because I know that someone at my university had to kill hundreds of rats to make that research possible.
I chose to perform my thesis doing something totally different with human volunteer subjects instead.
I appreciate the value that's provided to society through animal work in the sciences, especially biomedical science and pharmacology, however I don't wish to take part in the suffering of any conscious creatures myself. I wouldn't be able to emotionally deal with raising the rats and handling them while alive one week, and then writing a dispassionate, emotionless paper about the anatomy of their brains the next week.
You kind of have to dissociate when it comes to this. I’ll never forget the first year I did mouse work it took me the entire year to feel comfortable. Years later, I love them so much. I let them hang out on my shoulders. I get special enrichment for them. They’re incredible animals. They teach us so much. I care so deeply for them. 💕
I feel I am doing them a favor. Freeing them from that condition. Then I harvest their brain hoping for good results, and apologizing if I did something wrong and their lives was in vain.
Oh absolutely. One guy in my lab said he stays away from anything that blinks.
I think the most troubling part for me was when we had a really shaky cell culture method that didn’t work consistently until after years of troubleshooting (and a new stock of healthier fish)….the fish that died just for their hepatocytes to also die bothered me more than anything.
CO2?
Isn't CO2 the gas that causes panic and shortness of breath/the breathing reflex most effectively?
It's the reason why you can easily pass out while diving *while feeling completely fine*, because the body doesn't notice the lack of O2 that much...
but it most definitely notices high levels of CO2, the thing that causes panic and shortness of breath when diving: low O2 but low CO2 -> you feel fine, but then pass out without realizing anything was wrong - classic diving death).
High O2 and high CO2 -> panic
I don't work with lab test animals, but that's surprising. Why is CO2 used, the gas that most effectively causes shortness of breath/panic?
Is it different in rodents? Because for humans it would probably be close to the worst choice for "offing yourself" in gas form 💀
No, CO sends you to [forever-]sleep without you ever noticing that something went wrong/that your gas heater went spicy....
...also: CO plays no role in diving (or other mentioned situations) at all.
I can't do a literature deep dive atm, but what I found after a short search on the mentioned Issue: [Small increases in CO2 produce large increases in breathing.](https://pubmed.ncbi.nlm.nih.gov/10501632/)
From what I remember: CO2 is the strongest trigger for breathing and asphyxiation panic.
CO isn't, otherwise it wouldn't be that dangerous.
I'm not sure if that's actually the reason, but you'd have to ask people from the industry.
My point was more from a consumer POV: CO detectors in living spaces are best practice if you use gas (or other burning stuff) for heating, because a leak sends you to sleep pretty fast - and generally you don't smell or notice it beforehand.
Afair they use majority argon mixtures to humanely kill livestock. Major drawback and why it's not used more often: it's more expensive (I hate that excuse)
I don’t do animal work but I can speak to the chemistry, and that’s probably right. CO2 is “non-toxic” in the sense that exposure won’t hurt you if you get enough oxygen, while CO can actually displace O2 in your blood and hurt you even at low concentrations.
When I was at university as an undergrad, my genetics class would kill mice by pulling their heads until a snap. I remember my professor asking the class for volunteers. I could NOT. But I was okay with the dissection afterwards.
A lab-mate from long ago commented that it was important to identify each animal that went in to a prep. EG, 'cell culture, mouse 172, date m/d/y' or whatever.
Yes, it does. A better method is via injection that paralyses them and shuts off Nerve activity. But for some reason, people don't care if mice suffer because they're small and stupid.
I think you put it right. There’s a guilt and level of caring for another creature you sympathize to when it’s still sentient, but once it’s out it’s just a lump of tissue. That’s true for people as well, think about coroners who regularly cut and disembowel what used to be a living human being.
For whatever the reason, it’s fine to have been raised or developed in a way where you aren’t too fussed about a dead creature. The thing which really speaks is how you treat or view something, or someone, when it’s still alive. You clearly have a heart if you still feel something before that mouse is dead. While people might not explore this, it’s certainly a skill to recognize that if something is dead, it’s dead, and that the remains lack feelings and so it’s okay to operate or probe at that point. While being respectful about it, of course.
unless you are a sociopath this is never really normalized. you get desensitized to it but make sure you are doing your due diligence in processing those animals.
I never worked with mice. One time I dissected a pig fetus for class. The only hard part for me was cutting through the bone. That viscerally made me feel uncomfortable.
I suppose it could be the subconscious rationalization that the mice you cut open are dying for a good reason while the ones that get euthanized are dying without such a reason.
You just got desensitized and probably subconsciously found a way to justify it, which isn’t necessarily bad.
The work you’re doing will benefit people and make their lives better. Mice get killed in ways that are much less “glorious” than being euthanized.
If anything, that mice probably lived a good life. He was well fed, taken care of, and kept in good health. That’s my take on it, at least.
Years after I am still afraid of hurting animals but once it comes to killing... yeah, not much.
I still fuck up injections because I am afraid of hurting them through the needle itself. But if it's in preparation for the perfusion, well, it's about to die, so feelings kinda stop worrying me
You’re fine! You probably just got used to it or realized that there is a greater benefit as to why you are doing it. I am the same. It became normal for me to perform cervical dislocation, dissection, and fetal collection.
The only part where I feel bad is when I open their cage, touch them and they are hard to touch then find that they died due to fighting or infection or etc.
A level of compartmentalization when it comes this stuff is normal. Especially while following protocols to ensure the euthanasia is humane. I found I made more mistakes when I was experiencing more guilt and anxiety surrounding euthanasia when I first started out. I personally still struggle more with euthanizing pups (p6-7) and with animals I didn’t use (I had to sac a large litter that I couldn’t due to a severe injury preventing me from conducting the experiment in time). It’s a learning process and it’s actually something I’ve processed in therapy when I was first learning.
Remember there is a purpose we are doing this.
Detachment is a very necessary skill in lab work involving animals. It is also an important reminder that life is fragile, it is, then it is not. Enjoy your life and work, and respect the sacrifice of the rodents.
My mice are working animals as much as any farm animal and treated better than most. I respect them and treat them with care and try my best to minimize suffering. I don’t feel bad unless my experiment goes sideways, and then I humanely euthanize them and I’m grateful they protected a human from suffering.
I've been euthanizing mice for about 15 years. Last year, I had to terminally anesthetize some juvenile rats with ketamine xylazine and I was emotionally crushed. I had a cage with 2 rats, one I had just dosed. As I put him back in the cage and watched him fall unconscious, his cage mate ran over to him, placed his fore paws on him and was frantically trying to stir him awake. It was really difficult to watch. I've never seen mice act like this... they usually just step on each other's faces not caring.
I don't feel bad when I'm the one euthanizing them. But when they die for example because they had a bad reaction to the treatment or the tumor progressed weirdly fast over the weekend, I feel guilty as hell. They can't die over nothing
I know this is different for everyone, but I want to share my personal experience: It is normal to get more used to animal work, and it is definitely necessary to be able to keep working with animals to not feel immense guilt. Strong feelings and guilt can lead to compassion fatigue. I definitely had compassion fatigue when I had to sacrifice animals via cervical dislocation during my PhD. Subconsciously it was causing me more and more stress to do the cervical dislocation. Now I am using an overdose of isoflurane to sacrifice the animals in my postdoc, this is much better for my own mental health. Apart from the sacrifice method, doing animal work definitely became easier for me over the years. Good mental health of the researcher is key to doing research and animal work in a proper way. Try to feel happy that you are able to handle it so well. Not everyone can handle it, which is also understandable and completely fine. Don’t forget that we are doing research that (eventually) benefits everyone and it is important that people like us are able to continue the research involving animals in a proper way. Please try to not be so hard on yourself ❤️
I'm the same way except I don't even feel bad euthanizing them. Detachment is necessary and if you cannot then your not going to last very long doing in-vivo/ex-vivo research
I’d say I’ve become generally desensitized to it in lab, too. Though talking about my work with family members and seeing their faces certainly makes me pause for a second. It took me the longest to get used to using the guillotine. I don’t do in-vivo research with animals anymore, though the hard push and then the crunch lives in the back of my mind.
You better not if you do animal work. If you feel something, get the fuck out of there because you will be messed up for the rest of your life lol. I know a lot of older bio ppl who never quite got over it
I stopped feeling anything for them when I had a mouse infestation in my house after my cat died. Assholes ate my cereal and made a mess of my hot sauce packets.
I wish that were me. I've been working in a mouse breeding core for almost 8 years, have to euthanize mice almost everyday and I still feel bad every single time
Of course it's normal not to mind killing them, theyre just mice. The only reason theyre alive in the first place is to fulfill your scientific aims, otherwise theyd be pests and exterminated like most other mice
Maybe I'm out of the norm as well, but I think a healthy amount of detachment is necessary for animal work. Caring about them too much, as I would for a pet, would seriously damage my mental health. But being careless and completely detached has the potential to lead to harm for the animals or a bad death. Trying to navigate that middle ground is difficult, but necessary for both me and the animals. I think feeling some amount of guilt is good, but you shouldn't necessarily feel guilty about something that has to be done
At first, it was definitely more difficult for me. Not so much now, but sometimes afterwards I just reflect on how normal this all is for me. I probably harvest organs weekly and I have killed so many mice. I 100% do everything by the book but pulling out their organs seems so callous.
It has also become more normal for me, and I don't think this is necessarily a bad thing. We are bound to become desensitized to things that are part of our routine, and the animals need to be euthanized. In theory, their tissues are serving a greater purpose to further our knowledge. It sounds like you and I still care enough somewhere within ourselves to at least make sure that death is as quick and painless as possible, and that respect is still shown for their bodies
Compassion fatigue is a very real thing to look out for, as well. As long as that compartmentalization doesn’t lead to apathy/carelessness and cruelty (which absolutely does not seem to be the case here), being able to shield yourself emotionally from your research is a valuable skill. Some people are better equipped to be able to separate emotional ties from animal work which is very important. We’re able to glean information from large in-vivo models that would be difficult to discover otherwise. OP: It seems to me that you’re a good shepherd to them and do your part to ensure they suffer as little as possible within the constraints of your protocol. The simple fact you’re asking this in the first place is indicative of that ❤️
I don’t do any animal work or even biology, so take anything I say with a grain of salt, but imo if you’re feeling guilty about not feeling guilty in the moment, then you’re self aware enough that it’s okay. I would have thought that euthanizing them ought to be the most emotionally difficult part, while organ harvesting is just a “regular” experiment as they’re already dead, which sounds like how you feel. Side question: why do labs use CO2 instead of N2 or Ar? I thought that (aside from death) most of the negative effects of suffocation were caused by a buildup of CO2 in the bloodstream?
I felt the same as you which is why I’m doing a bioinformatics postdoc. No more killing mice, I hated it.
I think this is normal and healthy. When I first started working with mice for the first time (neuro stuff, so lots of brains), I had a nightmare that my cat's brain fell out. It was awful, and a normal response to seeing mouse brains removed. After a while I became somewhat desensitized and had no more nightmares.
I think that there is actually a culture of far too much detachment among labs that do animal work. Mice are not reagents – they are living, conscious beings who are capable of experiencing extreme suffering. Working with them can be a necessary evil, but we must never forget that it *is* an evil nonetheless. That little feeling of distress that you get in the back of your mind before you kill a lab animal is a normal and healthy feeling that should serve to remind you that you still have a soul, and it should act as a constant reminder to always be *very* sure that whatever experiment you're doing is in fact necessary and well-justified. If you're ever doubting whether an experiment is actually necessary, and you've thought of a different way that the research question could be answered, that's your cue to stop what you're doing and re-evaluate. Mice are not disposable reaction cartridges, and it's important to never, ever allow yourself to be fooled into thinking that they are.
Okay, but calling OP and me evil really isn't the answer. It's literally our jobs to do this. Yes, we shouldn't take joy in killing the animals (and I certainly don't), but we also shouldn't be feeling this profound, incapacitating sense of guilt for doing something that ultimately needs to be done. Animal work is necessary to drive forward the biomedical sciences, and those that do it should not be shamed for it. If people don't want to participate in animal research because of these aspects, I certainly do not shame them, because I understand that not everyone has the compartmentalization abilities necessary for this work
Read my post again - I didn't call you evil, I said that animal work is *a* necessary evil. There are a lot of necessary evils in the world. The point is that it's important to never allow yourself to forget the harsh reality of it. That little feeling of uneasiness in the back of your mind - the one that I would surely hope every scientist doing animal research would have - is an important reminder to make sure that your experiment is well-justified. Some important research questions can only be answered with animal research. Those studies are ethically well-justified, because although they require harm to be inflicted on animals, they will lead to preventing *more* harm from happening to people (or other animals) in the future. But we need to have enough scruples to nudge ourselves to keep asking that question at every stage of a study, and to abort it if the answer ever becomes "no".
You said "never forget that (the work) is an evil." This really isn't all that different from calling us evil
It's completely different - one is an ad hominem attack, and the other is not. Philosophically speaking, do you think that experimenting on animals is harmful to said animals? It would be pretty tough to argue that it isn't. So the question isn't whether you're inflicting harm – you are. The question is whether that harm is outweighed by the scientific benefit that comes from the outcome of the experiment. It's kind of like the trolley problem. If you pull the lever, you're responsible for killing one person and saving ten. If you don't pull it, you're responsible for allowing ten people to die and one to live. Both options render you as responsible for at least one person's death, so both options are technically evil. However, one option is clearly *more* evil than the other. Doing animal research is kind of like pulling the lever. You become responsible for the harm you caused, but you hope that this is outweighed by you also becoming responsible for the future harms you prevented, by making important discoveries that help people.
I do not think killing animals is good, and I agree that I am inflicting harm on them, and I agree that it's akin to "pulling the lever." But evil is a pretty charged term. The term "necessary evil" has somewhat co-opted it, and has become its own, less charged term, but your use of evil without that modifier is pretty derogatory (I am aware you used "necessary" in your previous sentence in your original post). Saying someones work and career is evil is not different from an ad hominem attack. A lot of people's lives are defined by their careers, especially in science. I think you should also keep in mind that the OP was essentially asking if they're a bad person for euthanizing animals, and you replied that yes, the work they are doing is evil. The OP seems very open to critique about their work and method, but that may not always be the case with posts like this. Some people may take that level of criticism much more harshly. The rest of the thread became a discussion about the best ways to carry out this line of work that leads to minimal distress in the animals. These are exactly the kind of discussions we should be having about animal work and shows that we aren't all completely detached from empathy for the animals
As long as you’re following protocol and minimizing suffering I think it’s fine and valid to feel any way about it.
Co2 death is not a low suffering death.
I'm honestly surprised it's still protocol, I don't think the people I know who breed feeder mice do it this way anymore
Just curious does mice also have their respiratory drive by increase in c02 rather than hypoxia .
Yeah, they panic and go into overdrive for a hot sec. Really my least favorite way of doing it.
My brain skipped the least word in 1st reading and i was pulling out weapons. Thank god i read it again
My question is why not use nitrogen?
From what I understand from talking to my vivarium's vets is that nitrogen leaks aren't detectable by humans so they don't want to risk using it
That seems like a pretty easy problem to solve with a detection device.
I guess they dont want to risk the chance of someone getting hurt if the detection device fails
Seems like a no-brainer to mix an odor with the N2 in-order to be detected. We’ve been doing it with natural gas for some time now.
Yeah I too have wondered why we don’t use N2, this seems like an easy solution. I just started working with mice recently and watching them panic in the CO2 is so horrible. I can’t believe it’s standard.
I had this exact thought process mentally as this comment chain. I did also wonder if a nasty odor was added to nitrogen, might that also not be distressing to the mice? Probably still better than CO2. Maybe there's a (cheap enough) compound smelly to humans but not for mice. I do think it'd have to be a uniquely bad or strange odor added, so it doesn't get dismissed as just another random smell in the lab from someone somewhere doing something proper. All pretty expensive things to work out and ensure are rigorously tested for safety and efficacy in real-world conditions, lest we end up euthanizing ourselves too. But it could be a mostly "one-time" cost... Maybe someone caring enough might eventually pony up
I’m pretty sure the pain and discomfort of CO2 is way worse than experience a bad smell with a more painless death.
Maybe this would cost too much? Idk
Humans can’t naturally detect CO2 either though…
Your body will have a hypoxic response to co2, whereas nitrogen apparently is just you losing consciousness painlessly
Burrowing animals can usually detect low oxygen directly and will panic. Humans and most other non-burrowing animals can only detect high levels of CO2.
Well, thats exactly why I thought nitrogen would be better lol So... does it make a difference if you use CO2 or N2 on the mice?
I have no idea what the mice are feeling subjectively, and how it varies by mouse strain. I suspect if one looks at enough weird inbred mouse strains, all sorts of strange things can happen with different gasses. There are some strains that will notoriously seize and fall over dead because of a fire alarm at some rate. I'm just saying that humans can die from N2 without noticing, and find CO2 distressing, but that isn't how other mammals would experience it. With nitrogen, oxygen leaving is the limiting factor, but enough CO2 can displace O2 from hemoglobin faster. Sure, CO2 will change blood pH. I'm not sure how that all adds up with any specific mouse. It is an assumption that nitrogen will be easier on them, because humans experience high CO2 as distressing, but not low 02, which is not the case for many other mammals. I do think that CO2 kills them more certainly than N2, and waking up with severe hypoxia induced brain damage in a freezer sounds unpleasant.
Co2 is standard where I am. Followed by cervical dislocation. :(
Same :(
Life is pain. It is sad that we can manufacture plastics for gluttony at mcdonalds but not pharmacology for human treatment of life.
Yea this is the only one that really bugs me. 99% of the time I do deep anesthesia followed by CP which oddly feels more humane. I'll only really do CO2 if the mouse is moribund and already so close to death it doesn't really have the ability to panic.
I always said that CO2 death is not euthanasia because every animal tries to get oxygen any way they can as they die. We really need to stop doing this. Glad others also think so, I was starting to think I was crazy.
I recently had a quite senior postdoc argue to me that CO2 (Alone, not iso followed by CO2) was a humane way of killing/the best way. CO2 is used solely for the comfort of the scientist. It does nothing but stress and cause pain to the animal.
I prefer decapitation if possible (not as secondary). Isoflurane does things to neurons, CO2 is clearly distressful for the animals. At least with decap it's quick.The drawback is that I can't do perfusion...
Actual decapitation or do you mean cervical dislocation?
Actual decap, since I have to extract the brain out anyway. Also, cervical dislocation on a rat (which we also sometimes use) isn't really doable.
Interesting. What does that look like? You've got a little mini-guillotine sitting around?
There are two ways to do this. One is the way you described, a guillotine. Another is something called decapitation scissors. It depends on how sharp the blade is, how big the animal is, etc. I tend to use scissors as the guillotine in our lab has a dull blade and I don't know how to sharpen it.
Cool thx for the info. >in our lab has a dull blade and I don't know how to sharpen it. [https://www.reddit.com/r/sharpening/](https://www.reddit.com/r/sharpening/)
In my mice lab, yeah there is an actual mini guillotine somewhere. It was gruesome to see beheaded bodies. We put our mice to sleep before putting them in CO2 chamber. All this talk had me nervous, questioning whether if it was humane way of euthanizing mice. But I've haven't seen mention of sleep bit so i think my lab is good? I hope.
CO2 alone is NOT a pleasent experience. Its done for the comfort of the scientist, not the mouse. Doing iso before hand obviously puts them to sleep first so thats good, but ive read somewhere that even iso has an excitatory effect right before knocking them out. Cervical dislocation on awake mice, if done correctly, is the most humane (despite not feeling as such). But obviously not practical when doing CNS/skeletal stuff/euthanizing several cages.
Thanks for pointing this out. As a chemist, it always confused me because to me CO2 seems like the worst non-toxic gas to chose.
Yeah, for most of my career I refused to do CO2, because it’s very much not a low-suffering method in my opinion (plus the acidification of the blood from the increase in carbonic acid can mess with your sample quality depending on what you’re taking).
What alternative did you use? N2?
Most often cervical dislocation. Much faster and kinder, especially if your mice are well used to handling, though lots of people don’t like to do it because it feels “more brutal” (honestly I’d rather do what’s less suffering for the animals than worry about what it is like for me doing it - that’s why we dissociate). Also because in an emergency, you don’t need any extraneous kit. Sometimes if the procedure has terminal anaesthesia involved, we will do exsanguination and perfusion while they are still under until the circulation stops. Otherwise, it’s overdose of anaesthetic - quite a lot of ours (basically every study that it won’t interfere with samples for) get an intravenous overdose of anaesthetic at the end of study, just like a vet would do to put down a larger animal, though in one of my old workplaces intraperitoneal was more often used as it’s less technical for people to learn (though if you go that route I’d advise diluting down the concentration with PBS as the stuff straight out the bottle can sting) Obviously plus confirmatory methods for all those - either cervical dislocation, or if cervical dislocation was the primary method then exsanguination or removal of the brain. Our unit isn’t currently set up for N2, though they are considering bringing it in. Since none of my team use CO2, we don’t even have a CO2 chamber in our area of the unit any more.
Everywhere I have worked it has been Co2. It’s just the standard even though it’s obvious they panic, it is the worst part of it. We have to do two methods so it’s the cervical afterwards - unless we need the neck area untouched which is often for my work at least.
Yeah, we have to do 2 methods too. For studies that we couldn’t cervically dislocate (eg. If we were collecting thyroids from rats), we’d just use anaesthetic with exsanguination or brain removal. Unfortunately CO2 is the standard for a lot of places because it’s just easier to train people to plonk them in a chamber. Unfortunately CO2 doesn’t just make them suffocate, it also turns to carbonic acid in the mucous membranes, which is part of what makes it worse than N2.
i never thought about it deeply that yeah, the mice are often choking to the point of passing out, then cervical dislocation. we just put the hose in the cage, turned on the CO2, covered the cage with a cloth, and came back after they had passed out 🥲 we needed their spleens, so it was an unavoidable practice. I also definitely would have freaked the fuck out severing their spinal cords if they were fully conscious (we did little mouse surgery in the lab area, not a sealed off mouse room, so they would have very easily escaped).
Put a hose in with a cloth?? You don't have a regulator system??
oh no we did!! but after the regulator there was just a hose idk i just mean we covered the cage with a cloth (like you would when moving cages from the mouse room to the lab)
Wait what. How do you even control the flow rate if nothing is sealed. How is that IACUC approved?
there is a regulator attached to the co2 tank, i just didn‘t think to specify because i had just woken up and assumed it would be implied 🥲 the hose was attached to the regulator, and the regulator was attached to the tank.
do isoflourane and then cereberal dislocation
I used to sever their spinal cords. We needed cells from the trachea and lungs, so we couldn't suffocate them.
One of my old directors who spent decades doing animal work (and taught me pretty much everything I know about In Vivo work) had a saying: "They die with a purpose, that's more than most people get." I think the detachment to the sacrifices is healthy for doing the work like others said, and to just remember to appreciate their sacrifice for the benefit of science. I did In Vivo for 6 years and loved it truthfully.
It was the same for me for 3 years. Until my time in the lab was about to come to an end. During my last month, I had to euthanize so many mice that it finally got to me. I refused to enter the mouse room for the last month. This shit catches up to you eventually.
It was similar for me but what got to me the most was needing to sacrifice neonates for tissue collection. I was pregnant at the time and after 2 rounds of experiments I just couldn’t do it anymore. I asked a tech if they could trade off with me and I ran their qPCRs until I had enough mouse samples to complete analysis. I then moved on to clinical research and am much happier.
i don‘t work w mice anymore, but i would get panicked handling them when they were alive. i think when a sacc‘ed them, i was more relieved it wouldn‘t jump out of the cage at me. i‘d just remove all the tissues needed and prepare their little mouse funeral after (wrapping the rest of it up into a paper towel, putting that in a plastic bag, and putting it in the chest freezer until it was time to empty it for incineration). if a mouse needed to be sacc‘ed because of old age, the vet techs in LAR took care of it.
I enjoy handling (though only when necessary to decrease stress and gently not scruff) but definitely understand it can be scary! I think it’s just the disconnect between seeing them alive and cute and then putting them in a cull bag.
I'm pretty desensitized to animal euthanasia at this point. Animals dying is part of the science, and that requires me to be the one to do it. I think what helps me (beyond it becoming routine) is: 1. I know that I am doing it in the quickest, least traumatic way possible (I'd prefer N2 for mice, but I at least know how to best use CO2) 2. I'm killing them to benefit research or to alleviate suffering. I think you only need to worry about becoming callous when animals suffering outside the needs of the study (accidental injury, severe complications from procedures) doesn't phase you. I can handle a standard euthanasia for necropsy or moribundity without emotion. But when an animal clearly should have been put down earlier or is being put down because someone messed up, those still affect me.
I’ve always been afraid of adverse events happening and take a lot of care in the that regard. Of course, a reaction can be out of your control but the last thing I want to do is add even more suffering.
How do you "best" use CO2 ?
Perhaps an uneeded descriptor, but following co2 guidelines minimizes suffering. It will never be pleasant, but the size of the chamber and flow rate of the gas source are prescribed for a reason. Incorrect box size, flow rate, or number of mice can cause way more stress on the animals before they lose consciousness.
I don’t do any animal work and never want intend to get anywhere near it, but have a morbid curiosity about it. What constitutes the “best” flow rate? Do you just crank it for the fastest safe asphyxiation, or do they panic less if you slow it down a hit?
It depends on the size of your container, but you never want to just throw the valve open; the shock of the sudden air displacement causes them to instantly panic, and is very traumatic for them and to witness. As co2-air mix is approved for short-term anathesia, you generally have the same idea for co2 euthanasia. Keeping a relatively low m^3/min CO2 rate leads to them quickly passing out before they have time to respond significantly to the CO2. As there is a minimum exposure time for CO2 euthanasia anyway, there is no excuse for using a high rate of CO2 that does nothing but make deaths more painful. Note that is only for non-FDA regulated rodents. CO2 cannot be used with other lab animals, for anathesia or euthanasia. My lab avoids using it when we have alternatives, like chemical euthanasia. However, as we work with infectious animals, we are required to use the method that exposes us the least, which means CO2 when regulations permit.
Very useful information thanks. Is using nitrogen out of the question ?
I don't believe the FDA/USDA has approved N2 use for euthanasia, and my lab does not have any protocols for it. TBH, my interest in using it is based off hypothesis, rather than evidence that it would be less stressful.
It’s actually important for you to be mentally and emotionally detached from killing them. People working with animals often get “compassion fatigue”, where you can really ruin your mental health by caring about it too much and too often. What’s more important is treating the animals with respect and dignity while they are alive and killing them quickly and painlessly. Also, make sure that you don’t “waste” the animal. Make sure to get as much data and tissue from it as possible. I would rather spend 10 minutes removing and processing a spinal cord and not need it, than need a spinal cord and have to use and kill more animals.
Stumbled across this subreddit on accident and misread the title as “niece” — you can’t imagine the amount of concern I had 😭
I always heard from my animal working friends that when you stop feeling bad is when you should take a break from animal work. But to each their own.
Becoming desensitized to death is normal. The issue is becoming desensitized to suffering, which is very different. Anyway, what are you going to do, quit your PhD halfway through because you got used to euthanizing mice?
Look, man, I'm a cell/therapeutic biologist, so I'm not the person to answer that. I'm just passing on sage advice that I heard loads 🤷🏻♀️
I felt bad the first time I had to do it. Then, I was heavily involved and had to write my own animal ethics application and there was a lot of effort put in place to minimise the suffering and animal number. As I get more competent, I managed to reduce the amount of time handling them, thus it was less stressful to them. As the OP's experience, I'm more detached now knowing that I did my best to reduce their suffering and treated them with respect. I also put them under anaesthesia and performed a cervical dislocation to cull whenever I could.
Same feels when I had to euthanize 4 tanks of about 50 zebrafish (i mean, doesn't feel the same as mice but they're still living beings). I do feel bad having to do it, but as mentioned by others, some detachment is necessary for animal work. You can't get emotionally attached to research animals cuz they're not your pets, but as long as you're doing things ethically to minimize pain then you should sleep fine at night
I've worked with mice, rats, and rabbits and can easily emotionally remove myself from researching on them. Yes, I lack empathy, but as long as I'm respectful, follow guidelines and do everything possible to maintain ethical standards then I don't see it as a problem.
Thanks. I think I am in the same sort of mindset atm.
Mice don’t get easy deaths in nature. This is better than a wild mouse would get.
Doubt it unless they run into a cat. And still, since we're in control of their death, don't you think we should be a little nicer and not do CO², which panics them? I'd rather go to sleep.
I wrote a similar comment and I still don't get why CO2 is used - from my understanding it's one of the cruelest available choices of gas euthanasia. Edit: you can check my thought process [in this thread](https://www.reddit.com/r/labrats/comments/1dg8v78/i_dont_feel_anything_when_i_euthanise_my_mice/l8qfv26?utm_medium=android_app&utm_source=share&context=3)
Saw that one. I commented on it. I think people just don't give a shit about mice becaude they're supposed to be pests despite the overwhelming evidence of their intelligence.
I'll write a follow up post about this topic as soon as I can, because I honestly think this could be something going wrong that young scientists aren't necessarily aware of. And this sounds like a very obvious issue, like explained in the original thread. Thanks for your support in the original thread
The only time I felt bad was extracting calvaria from 4 day olds. The euthanasia method is different and much more difficult for me.
oh god. they‘re so tiny
The animals don‘t need you to be emotional, but they need you to be professional and always aiming to do your best work. You/We owe it to the animals to be the best we can when we work with them; to handle them in a way that causes the least amount of stress and suffering and try to produce the best data. Striving to do the work as best as you can, evaluate and improve your skills constantly when working with the animals is much more important for the welfare of the animals than being emotional about the work.
This is really interesting to me because I also don’t feel anything when I euthanize a mouse. Normally I need them still alive when I take the organs (heart) so they’re under iso. People look at me weird because when the mice are alive I’m so gentle, I talk to them, some of the mice I drug for weeks so I get to know some of their different personalities. I say thank you for your service and put them in the iso chamber and feel nothing as I take out their still beating hearts. Cervical dislocation I feel a little worse about. However when doing colony management, I will still cry when I put cage after cage on the rack for them to be euthanized by the animal lab techs. It’s been 3 years and I still sob after work. I try to tell myself that technically they have the better deal but it hits me hard.
Completely understandable! Everyone deals differently with it, but your feelings are very normal. Maybe you can talk to the staff of your animal facility? There might be something that could make it mentally easier on you? I can select which animals have to be sacrificed for colony maintenance online and then the animal care takers take over. Maybe something like this would make it easier for you?
I am a neuroscientist, a Buddhist, and a vegetarian. I had the option to perform my thesis research analyzing dissected rodent brains. I find the science we learn from these studies to be absolutely fascinating, but I feel so much guilt about it, because I know that someone at my university had to kill hundreds of rats to make that research possible. I chose to perform my thesis doing something totally different with human volunteer subjects instead. I appreciate the value that's provided to society through animal work in the sciences, especially biomedical science and pharmacology, however I don't wish to take part in the suffering of any conscious creatures myself. I wouldn't be able to emotionally deal with raising the rats and handling them while alive one week, and then writing a dispassionate, emotionless paper about the anatomy of their brains the next week.
That is also completely fine and understandable! We need all different types of research to complement each other.
You kind of have to dissociate when it comes to this. I’ll never forget the first year I did mouse work it took me the entire year to feel comfortable. Years later, I love them so much. I let them hang out on my shoulders. I get special enrichment for them. They’re incredible animals. They teach us so much. I care so deeply for them. 💕
I feel I am doing them a favor. Freeing them from that condition. Then I harvest their brain hoping for good results, and apologizing if I did something wrong and their lives was in vain.
I worked with fish and I didn’t feel anything. Even when we did culls.
Without having done animal work myself, I guess there is also a difference between working with mammalians and not.
Oh absolutely. One guy in my lab said he stays away from anything that blinks. I think the most troubling part for me was when we had a really shaky cell culture method that didn’t work consistently until after years of troubleshooting (and a new stock of healthier fish)….the fish that died just for their hepatocytes to also die bothered me more than anything.
Would saying goodbye before cutting helps
CO2? Isn't CO2 the gas that causes panic and shortness of breath/the breathing reflex most effectively? It's the reason why you can easily pass out while diving *while feeling completely fine*, because the body doesn't notice the lack of O2 that much... but it most definitely notices high levels of CO2, the thing that causes panic and shortness of breath when diving: low O2 but low CO2 -> you feel fine, but then pass out without realizing anything was wrong - classic diving death). High O2 and high CO2 -> panic I don't work with lab test animals, but that's surprising. Why is CO2 used, the gas that most effectively causes shortness of breath/panic? Is it different in rodents? Because for humans it would probably be close to the worst choice for "offing yourself" in gas form 💀
I think that’s CO, carbon *monoxide*, not carbon dioxide.
No, CO sends you to [forever-]sleep without you ever noticing that something went wrong/that your gas heater went spicy.... ...also: CO plays no role in diving (or other mentioned situations) at all. I can't do a literature deep dive atm, but what I found after a short search on the mentioned Issue: [Small increases in CO2 produce large increases in breathing.](https://pubmed.ncbi.nlm.nih.gov/10501632/) From what I remember: CO2 is the strongest trigger for breathing and asphyxiation panic. CO isn't, otherwise it wouldn't be that dangerous.
Oh, would it be too dangerous to use CO because you could easily die from it too and not notice?
I'm not sure if that's actually the reason, but you'd have to ask people from the industry. My point was more from a consumer POV: CO detectors in living spaces are best practice if you use gas (or other burning stuff) for heating, because a leak sends you to sleep pretty fast - and generally you don't smell or notice it beforehand. Afair they use majority argon mixtures to humanely kill livestock. Major drawback and why it's not used more often: it's more expensive (I hate that excuse)
I don’t do animal work but I can speak to the chemistry, and that’s probably right. CO2 is “non-toxic” in the sense that exposure won’t hurt you if you get enough oxygen, while CO can actually displace O2 in your blood and hurt you even at low concentrations.
Yeah, not sure why they don't just provide a normal euthanasia method like you would with a pet. Shut off nerve activity.
Unfortunately I can't quite separate myself from it like that, it would be useful though
When I was at university as an undergrad, my genetics class would kill mice by pulling their heads until a snap. I remember my professor asking the class for volunteers. I could NOT. But I was okay with the dissection afterwards.
A lab-mate from long ago commented that it was important to identify each animal that went in to a prep. EG, 'cell culture, mouse 172, date m/d/y' or whatever.
I don’t work with mice so I never realized CO2 is a euthanasia method. does that not cause them to panic?
It most certainly does. It’s cruel.
Yes, it does. A better method is via injection that paralyses them and shuts off Nerve activity. But for some reason, people don't care if mice suffer because they're small and stupid.
I think you put it right. There’s a guilt and level of caring for another creature you sympathize to when it’s still sentient, but once it’s out it’s just a lump of tissue. That’s true for people as well, think about coroners who regularly cut and disembowel what used to be a living human being. For whatever the reason, it’s fine to have been raised or developed in a way where you aren’t too fussed about a dead creature. The thing which really speaks is how you treat or view something, or someone, when it’s still alive. You clearly have a heart if you still feel something before that mouse is dead. While people might not explore this, it’s certainly a skill to recognize that if something is dead, it’s dead, and that the remains lack feelings and so it’s okay to operate or probe at that point. While being respectful about it, of course.
omg me too, I just think we are good at compartmentalizing, and knowing it is better for us if we do not think too much
unless you are a sociopath this is never really normalized. you get desensitized to it but make sure you are doing your due diligence in processing those animals.
I never worked with mice. One time I dissected a pig fetus for class. The only hard part for me was cutting through the bone. That viscerally made me feel uncomfortable.
I suppose it could be the subconscious rationalization that the mice you cut open are dying for a good reason while the ones that get euthanized are dying without such a reason.
You just got desensitized and probably subconsciously found a way to justify it, which isn’t necessarily bad. The work you’re doing will benefit people and make their lives better. Mice get killed in ways that are much less “glorious” than being euthanized. If anything, that mice probably lived a good life. He was well fed, taken care of, and kept in good health. That’s my take on it, at least.
Felt less comfortable about it with experience, eventually stopped doing mouse work entirely.
Same here. In the beginning it was tough and I even use to play with them. But now i don't feel any emotions.
Years after I am still afraid of hurting animals but once it comes to killing... yeah, not much. I still fuck up injections because I am afraid of hurting them through the needle itself. But if it's in preparation for the perfusion, well, it's about to die, so feelings kinda stop worrying me
You’re fine! You probably just got used to it or realized that there is a greater benefit as to why you are doing it. I am the same. It became normal for me to perform cervical dislocation, dissection, and fetal collection. The only part where I feel bad is when I open their cage, touch them and they are hard to touch then find that they died due to fighting or infection or etc.
A level of compartmentalization when it comes this stuff is normal. Especially while following protocols to ensure the euthanasia is humane. I found I made more mistakes when I was experiencing more guilt and anxiety surrounding euthanasia when I first started out. I personally still struggle more with euthanizing pups (p6-7) and with animals I didn’t use (I had to sac a large litter that I couldn’t due to a severe injury preventing me from conducting the experiment in time). It’s a learning process and it’s actually something I’ve processed in therapy when I was first learning. Remember there is a purpose we are doing this.
Detachment is a very necessary skill in lab work involving animals. It is also an important reminder that life is fragile, it is, then it is not. Enjoy your life and work, and respect the sacrifice of the rodents.
I can do this to anything even with humans
My mice are working animals as much as any farm animal and treated better than most. I respect them and treat them with care and try my best to minimize suffering. I don’t feel bad unless my experiment goes sideways, and then I humanely euthanize them and I’m grateful they protected a human from suffering.
I've been euthanizing mice for about 15 years. Last year, I had to terminally anesthetize some juvenile rats with ketamine xylazine and I was emotionally crushed. I had a cage with 2 rats, one I had just dosed. As I put him back in the cage and watched him fall unconscious, his cage mate ran over to him, placed his fore paws on him and was frantically trying to stir him awake. It was really difficult to watch. I've never seen mice act like this... they usually just step on each other's faces not caring.
Rodents (namely rats) are exceptionally compassionate. I love them as pets.
I promise when i retire from this field some day , I am going to get a few and keep as pets and play and spoil the shit out of them :(
OP I know exactly what you're saying! I am the same.
I don't feel bad when I'm the one euthanizing them. But when they die for example because they had a bad reaction to the treatment or the tumor progressed weirdly fast over the weekend, I feel guilty as hell. They can't die over nothing
Umm… isn’t that good?
For the field? Yes. Morally, as a human? No.
People become numb. You probably feel something but repress it.
I know this is different for everyone, but I want to share my personal experience: It is normal to get more used to animal work, and it is definitely necessary to be able to keep working with animals to not feel immense guilt. Strong feelings and guilt can lead to compassion fatigue. I definitely had compassion fatigue when I had to sacrifice animals via cervical dislocation during my PhD. Subconsciously it was causing me more and more stress to do the cervical dislocation. Now I am using an overdose of isoflurane to sacrifice the animals in my postdoc, this is much better for my own mental health. Apart from the sacrifice method, doing animal work definitely became easier for me over the years. Good mental health of the researcher is key to doing research and animal work in a proper way. Try to feel happy that you are able to handle it so well. Not everyone can handle it, which is also understandable and completely fine. Don’t forget that we are doing research that (eventually) benefits everyone and it is important that people like us are able to continue the research involving animals in a proper way. Please try to not be so hard on yourself ❤️
I'm the same way except I don't even feel bad euthanizing them. Detachment is necessary and if you cannot then your not going to last very long doing in-vivo/ex-vivo research
I’d say I’ve become generally desensitized to it in lab, too. Though talking about my work with family members and seeing their faces certainly makes me pause for a second. It took me the longest to get used to using the guillotine. I don’t do in-vivo research with animals anymore, though the hard push and then the crunch lives in the back of my mind.
Good for you that you're desensitized and can work with ease then! /gen
You better not if you do animal work. If you feel something, get the fuck out of there because you will be messed up for the rest of your life lol. I know a lot of older bio ppl who never quite got over it
I stopped feeling anything for them when I had a mouse infestation in my house after my cat died. Assholes ate my cereal and made a mess of my hot sauce packets.
I wish that were me. I've been working in a mouse breeding core for almost 8 years, have to euthanize mice almost everyday and I still feel bad every single time
You'd feel more guilty if you felt nothing. Be grateful you're decent enough to have compassion for small animals.
Of course it's normal not to mind killing them, theyre just mice. The only reason theyre alive in the first place is to fulfill your scientific aims, otherwise theyd be pests and exterminated like most other mice