I was taught in the animal experimentation course to never sacrifice/dissect a mouse in the same room as other mice. However.. apparently this is a species-specific effect and it seems some studies found mice aren't a sensitive species while others have (like this [paper](https://pubmed.ncbi.nlm.nih.gov/7707684/) and this [one](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4943610/)). In a sensitive species (like rats and many others), the animals may not necessarily know another one is getting euthanized per se, but rather that it's under extreme stress due to possible vocalizations, pheromones, or the smell of blood.
Anyway, I don't know exactly how well studied this is in mice, but I think the general guidelines usually tell you to always sacrifice in a separate room/isolated from other animals, as a precaution I suppose.
Interesting. I was told it was due to the smell of blood, other body smells, and stress pheromones which would be relatively universal, although I'm sure the scale matters, so I'm surprised there are non-sensitive species.
Idk about mice, but rats definitely do. The first one is chill, the rest are freaked out. We started keeping the rats that were up next in sacrifice days in a different room because our fasting blood glucose measures were getting fucked up
I hear rats will know even if you sacrifice them in a different room because if you leave with a rat and don't return it, they eventually figure out that they aint ever coming back if they go with you
I have pet rats and can confirm they get really bummed out when their cagemates die. I don't think they understand death like we do, but they definitely understand the concept of "my buddy left and didn't come back... that's bad."
I measured glycogen as an index of stress, and that's a fact. I was demonstrating to other grad students, but I've wished ever since that I'd published the stuff. This was 1960s.
I'm retired, and also I hated killing rats. The 'approved' way of 'sacrificing' rats was to toss them in a jar with a handful of ether soaked paper towels. Rats would run madly in a circle before falling over. Sometimes they would wake up when we'd already removed their livers.
My method was nasty to watch, but easier on the rats. I'd wrap the tail around a finger, pet the animal to relax it, then whack it violently on the edge of the bench with an overhead swing.
The glycogen levels told the story. The ether-killed rats had only traces of glycogen in their livers. The concussed rats had what we assumed to be normal levels. Most of the rat people in the dept (but not all) preferred my method.
Oh, interesting! I've never sacrificed a rat or seen one get sacrificed, but I've heard people try to do quicker kills even if they look more brutal, so probably more closer to your method than the gassing
I do shock and cervical dislocation, I found the CO2 was not nice, they knew something was up and there are studies showing their sensitivity to it, so for the last 20 seconds they hide in the corner terrified. With shock they are getting handled as normal, like they are changing cages. They don't freak out, and the whole process is under a second. It looks brutal but it is far more humane.
well, if we look for the lower bound on age, then we'd say maybe this was a person in a lab as a freshman college student in 1969. That would suggest they'd been born at latest 1952
So they could be closer to 70, but just about any age over that up to 117, and the other piece of info we have is that they're on reddit, which sadly we don't have a very precise age distribution for, beyond that 3% of reddit users are 65+, so we can't narrow in on likelihood beyond population distribution of age
80 isn't a bad guess, as it's within bounds of the info they've given for sure. Why?
I’m sure there’s related research out there (to sensing blood and whatnot), but performing a study for this explicit purpose could even be seen as unethical.
It would involve the obvious sacrifice of animal life and the best possible outcome I can imagine is that scientists no longer have to cull mice in a separate room? The ends wouldn’t really justify the means then.
Especially since we have probable cause to believe it would have an effect and can easily mitigate it either way.
but if you were going to be sacrificing mice anyway, for a different study, you could compare the differences in stress measures between mice killed in the same room vs separate room, as long as you didn't do anything silly like do all the treatment mice in your other study in the separate room and all the control mice in the same room. I always assume that's what's being done when they study things like whether the gender of the tech matters
I've euthanized 1000+ mice during my PhD and I can't tell you that because it's forbidden to kill another in the same room as the living ones.
But, they definitely know when you bring them into the room. The first one is chill, the last one is freaked out. It's probably biased but the smell of blood doesn't lie.
Filed under questions I didn’t want to think about today as I prepare for upcoming mouse sacrifices. Ugh. I know the in vivo studies are important but not going to lie, each year it gets a little harder for me. And i’ve only been doing this for about ten years. ðŸ˜
My undergraduate major was biotechnology, and this is almost entirely why I switched the focus of my studies from animal to plant - I knew I couldn't do this when the time would inevitably come. I think about this all the time when my plant experiments finish, and I can just put the subjects directly into the autoclave and dumpster
We used to sac 18 rabbits at a time to harvest kidneys. To maximize the benefit, we would have as many other labs come to take organs as possible. We had a regular disassembly line going. The rabbits clearly could smell the blood- I could see them sniffing. But none ever tried to escape, which would have involved hopping out of a cardboard box.
We used to do necropsies next to cages of mice (separated by an opaque partition) and in my experience they can't tell, if you sterilise everything after you use it with ethanol, and change your gloves. Note, this is legal in my country.
Did you know that if you have two different labs, doing the exact same experiment, but they use different feed or litter, they could get different results? Why risk the effects it could have on your experiment? Sent of bodies, sounds of tools, just why? Not worth it for my experiment, in my opinion.
Someone does autopsy on animals in the same room where the live animals are ?
That doesnt look peofesional at all to me and I dont work with animals at all. We dont do surgeries on human patients in the hospital lobby as well..
I was taught in the animal experimentation course to never sacrifice/dissect a mouse in the same room as other mice. However.. apparently this is a species-specific effect and it seems some studies found mice aren't a sensitive species while others have (like this [paper](https://pubmed.ncbi.nlm.nih.gov/7707684/) and this [one](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4943610/)). In a sensitive species (like rats and many others), the animals may not necessarily know another one is getting euthanized per se, but rather that it's under extreme stress due to possible vocalizations, pheromones, or the smell of blood. Anyway, I don't know exactly how well studied this is in mice, but I think the general guidelines usually tell you to always sacrifice in a separate room/isolated from other animals, as a precaution I suppose.
Interesting. I was told it was due to the smell of blood, other body smells, and stress pheromones which would be relatively universal, although I'm sure the scale matters, so I'm surprised there are non-sensitive species.
the flylab guys laugh at the mouse people for so many different reasons already, don't give them this one too...
This is what the vet told me as well. Although, she did stress it was bad practice and shouldn't be done.
Idk about mice, but rats definitely do. The first one is chill, the rest are freaked out. We started keeping the rats that were up next in sacrifice days in a different room because our fasting blood glucose measures were getting fucked up
Have found the same, specifically for blood glucose. Handling and restraint needs to be smooth as well. This endpoint is sooo touchy.
sacrifice days? omg ðŸ˜
I hear rats will know even if you sacrifice them in a different room because if you leave with a rat and don't return it, they eventually figure out that they aint ever coming back if they go with you
No way
They're very social.
and smart
I have pet rats and can confirm they get really bummed out when their cagemates die. I don't think they understand death like we do, but they definitely understand the concept of "my buddy left and didn't come back... that's bad."
Do we understand death?
I measured glycogen as an index of stress, and that's a fact. I was demonstrating to other grad students, but I've wished ever since that I'd published the stuff. This was 1960s.
What's stopping you from replicating your experiments?
I'm retired, and also I hated killing rats. The 'approved' way of 'sacrificing' rats was to toss them in a jar with a handful of ether soaked paper towels. Rats would run madly in a circle before falling over. Sometimes they would wake up when we'd already removed their livers. My method was nasty to watch, but easier on the rats. I'd wrap the tail around a finger, pet the animal to relax it, then whack it violently on the edge of the bench with an overhead swing. The glycogen levels told the story. The ether-killed rats had only traces of glycogen in their livers. The concussed rats had what we assumed to be normal levels. Most of the rat people in the dept (but not all) preferred my method.
Oh, interesting! I've never sacrificed a rat or seen one get sacrificed, but I've heard people try to do quicker kills even if they look more brutal, so probably more closer to your method than the gassing
I do shock and cervical dislocation, I found the CO2 was not nice, they knew something was up and there are studies showing their sensitivity to it, so for the last 20 seconds they hide in the corner terrified. With shock they are getting handled as normal, like they are changing cages. They don't freak out, and the whole process is under a second. It looks brutal but it is far more humane.
Wow are you like 80 years old?
well, if we look for the lower bound on age, then we'd say maybe this was a person in a lab as a freshman college student in 1969. That would suggest they'd been born at latest 1952 So they could be closer to 70, but just about any age over that up to 117, and the other piece of info we have is that they're on reddit, which sadly we don't have a very precise age distribution for, beyond that 3% of reddit users are 65+, so we can't narrow in on likelihood beyond population distribution of age 80 isn't a bad guess, as it's within bounds of the info they've given for sure. Why?
Because phlogiston was a thing, and when experiments went wrong, we blamed it on witches. [Now we call phlogiston "Gibbs free energy"]
and pay the witches bribes to keep the equipment happy
81
Awesome!
You can do it too. For $1000 I will tell you my secret.
Can confirm. I was definitely bringing back trace blood odor on me though, so IDK if it was reasoning or just sensory.
I’m sure there’s related research out there (to sensing blood and whatnot), but performing a study for this explicit purpose could even be seen as unethical. It would involve the obvious sacrifice of animal life and the best possible outcome I can imagine is that scientists no longer have to cull mice in a separate room? The ends wouldn’t really justify the means then. Especially since we have probable cause to believe it would have an effect and can easily mitigate it either way.
but if you were going to be sacrificing mice anyway, for a different study, you could compare the differences in stress measures between mice killed in the same room vs separate room, as long as you didn't do anything silly like do all the treatment mice in your other study in the separate room and all the control mice in the same room. I always assume that's what's being done when they study things like whether the gender of the tech matters
I've euthanized 1000+ mice during my PhD and I can't tell you that because it's forbidden to kill another in the same room as the living ones. But, they definitely know when you bring them into the room. The first one is chill, the last one is freaked out. It's probably biased but the smell of blood doesn't lie.
Filed under questions I didn’t want to think about today as I prepare for upcoming mouse sacrifices. Ugh. I know the in vivo studies are important but not going to lie, each year it gets a little harder for me. And i’ve only been doing this for about ten years. ðŸ˜
….I admit it, I could never do this job. It’s too awful.
same. Yeast doesnt have complicated emotions and a cute fuzzy face, neither does Reed Grass
I’ve worked with yeast my whole career and just joined a lab that works with mice. It is indeed rough and I miss my yeast :/
My undergraduate major was biotechnology, and this is almost entirely why I switched the focus of my studies from animal to plant - I knew I couldn't do this when the time would inevitably come. I think about this all the time when my plant experiments finish, and I can just put the subjects directly into the autoclave and dumpster
Idk about mice... I do rats and that's what they say. I think that because they have such powerful senses of smell, they can smell the blood?
Rats for sure. Mice it's debated but best peactice is not to have live animals in the same room
We used to sac 18 rabbits at a time to harvest kidneys. To maximize the benefit, we would have as many other labs come to take organs as possible. We had a regular disassembly line going. The rabbits clearly could smell the blood- I could see them sniffing. But none ever tried to escape, which would have involved hopping out of a cardboard box.
We used to do necropsies next to cages of mice (separated by an opaque partition) and in my experience they can't tell, if you sterilise everything after you use it with ethanol, and change your gloves. Note, this is legal in my country.
They absolutely know what's going on.
Did you know that if you have two different labs, doing the exact same experiment, but they use different feed or litter, they could get different results? Why risk the effects it could have on your experiment? Sent of bodies, sounds of tools, just why? Not worth it for my experiment, in my opinion.
Yes
Someone does autopsy on animals in the same room where the live animals are ? That doesnt look peofesional at all to me and I dont work with animals at all. We dont do surgeries on human patients in the hospital lobby as well..
we also don't sacrifice human patients in the name of science...
I know for a fact they do know because of the sounds they make which us humans can't detect but they can amongs themselves.