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What is the point of culling mice? Should I be concerned?

6.7K views 15 replies 12 participants last post by  krazykritterz  
#1 ·
Before you read this, I just want to make it clear that I'm not biased, I just want a genuine answer. Anything said below is not intended to offend, I am just curious. Also it's my OPINION and NOT fact so please don't be offended, I respect your opinions too! Thanks! :)

Can someone actually explain to me the point of culling? I know the methods and I know that it's "to help the mother cope" or "the babies are weak", but surely the mother knows to kill the weak babies anyway? And even if they are weak, don't they deserve a fighting chance? My friend adopts baby mice bred to be snake food at 4 days old who are weak and raises them into strong, healthy mice. If "weak" babies are destined for death, then nature should be allowed to decide that process, I don't think their lives should simply be taken just because they don't start off as strong mice. I have a mouse who was at death's door when he was a baby, and with the right care and help, he made it through and is now 5 months old and living a happy, mousey life. Sure, it took some time, but it was worth it in the end, and he's no more weak than my other mice.

Also, rats can have up to 22 babies, and I never hear of rat breeders culling their pups. Surely domestic mice are more suited to coping with large litters anyway, as they are not having to do everything themselves (i.e. humans help them by making sure the temperature of the room is kept warm, we provide their nesting materials and they do not have to forage for food and water). I just genuinely couldn't ever do that. I'm not a mouse breeder as such, I am currently raising my first litter which wasn't planned (the mouse was pregnant when I adopted her).

Thanks to anyone who can answer. I honestly don't mean offence, I just want a non-biased explanation of culling and how it benefits. :)
 
#2 ·
Let's see, where to begin...

Have you ever seen a mouse (or rat) cull her own young? They start at the bellies and eat the young alive. If a pup is weak, I think it is surely kinder to put it down quickly and relatively painlessly rather then let it be eviscerated. Sometimes the does do NOT recognize the ill ones, and the babies will suffer until they die of malnourishment, anemia, megacolon, whatever their ailment is. It is terrible and painful, and as breeders who arranged their existence, it's our responsibility to minimize the pain they experience.

This view point could be applied to many domesticated animals. If a cow is dying in a field, you walk out and put a bullet in it to end it's misery. "Bison die in the wild" would not fly with the humane societies if the neighbors were to call you in for neglect. If a pet cat was to contract distemper, would you let it suffer until it passed naturally like its feral counterparts? In the UK, it is illegal to feed live mice to snakes, because humans have the means to minimize pain and suffering experienced by the mice by killing them more humanly.

Let's say a doe has a litter of 17. Maybe she could feed them all and raise them to adult hood, however, the offspring would probably be weedy, and if they were meant for breeding purposes, would have to be put on hold until they reach their optimum size. If not stunted permanently (Think of children who lack the proper nutrients and have long term mental and developmental problems).

Most mice breeders (here) have a specific goal in mind. They breed in large numbers to attain that goal, and if they kept every single mouse they produced, they would be over-run with mice. Even if they don't cull the mice when they are young (often the best option) they will have to cull them at some point, when there are no longer any benefits to the surviving mice.

I'll use my last litter as an example. My mouse had 8 pups, but only 2 of which were does. Males are pigs and will hog the milk, and I REALLY needed these does alive and healthy. By day three (when pigment comes in) I was able to see that 4 of the bucks were totally unnecessary to my breeding goals, so I was able to reduce my litter to 2 does, and 2 bucks. If I had left all the bucks in, I might have run the risk that my two does become malnourished and the doe cull the mice I REALLY needed.

But why not keep all the extra bucks and rehome them? Because bucks are smelly, and in the small amount of people out there interested in mice, even less of them are interested in adopting a buck.

The ideology of rat breeders is much different from mouse breeders, I would generalize that it is about "saving" animals and promoting rescues rather then improving a variety. I totally disagree with letting nature run it's course on domesticated animals that are clearly suffering.
 
#3 ·
Frizzle said:
Let's see, where to begin...

Have you ever seen a mouse (or rat) cull her own young? They start at the bellies and eat the young alive. If a pup is weak, I think it is surely kinder to put it down quickly and relatively painlessly rather then let it be eviscerated. Sometimes the does do NOT recognize the ill ones, and the babies will suffer until they die of malnourishment, anemia, megacolon, whatever their ailment is. It is terrible and painful, and as breeders who arranged their existence, it's our responsibility to minimize the pain they experience.

This view point could be applied to many domesticated animals. If a cow is dying in a field, you walk out and put a bullet in it to end it's misery. "Bison die in the wild" would not fly with the humane societies if the neighbors were to call you in for neglect. If a pet cat was to contract distemper, would you let it suffer until it passed naturally like its feral counterparts? In the UK, it is illegal to feed live mice to snakes, because humans have the means to minimize pain and suffering experienced by the mice by killing them more humanly.

Let's say a doe has a litter of 17. Maybe she could feed them all and raise them to adult hood, however, the offspring would probably be weedy, and if they were meant for breeding purposes, would have to be put on hold until they reach their optimum size. If not stunted permanently (Think of children who lack the proper nutrients and have long term mental and developmental problems).

Most mice breeders (here) have a specific goal in mind. They breed in large numbers to attain that goal, and if they kept every single mouse they produced, they would be over-run with mice. Even if they don't cull the mice when they are young (often the best option) they will have to cull them at some point, when there are no longer any benefits to the surviving mice.

I'll use my last litter as an example. My mouse had 8 pups, but only 2 of which were does. Males are pigs and will hog the milk, and I REALLY needed these does alive and healthy. By day three (when pigment comes in) I was able to see that 4 of the bucks were totally unnecessary to my breeding goals, so I was able to reduce my litter to 2 does, and 2 bucks. If I had left all the bucks in, I might have run the risk that my two does become malnourished and the doe cull the mice I REALLY needed.

But why not keep all the extra bucks and rehome them? Because bucks are smelly, and in the small amount of people out there interested in mice, even less of them are interested in adopting a buck.

The ideology of rat breeders is much different from mouse breeders, I would generalize that it is about "saving" animals and promoting rescues rather then improving a variety. I totally disagree with letting nature run it's course on domesticated animals that are clearly suffering.
Thanks for the reply, that's all the information I wanted to know. Could you tell me how to spot signs of illness? For example, how would I tell a mouse that is weaker than its siblings if they all look the same?
 
#4 ·
To be honest in my opinoun and dont even bother replying to change my mind. I breed on a tiny scale I have 1-2 male at a time and about 5 females. I breed one litter every month or 2. I also have 3 old does at the moment that are almost 2 and they are still here with me and ai am not planning on culling them.

About the if you don't have a use for something kill it. I would just give it away as a pet to someone who will let it live a life instead of being selfish and killing it because of your needs
 
#5 ·
Miceandmore64 said:
To be honest in my opinoun and dont even bother replying to change my mind. I breed on a tiny scale I have 1-2 male at a time and about 5 females. I breed one litter every month or 2. I also have 3 old does at the moment that are almost 2 and they are still here with me and ai am not planning on culling them.

About the if you don't have a use for something kill it. I would just give it away as a pet to someone who will let it live a life instead of being selfish and killing it because of your needs
Yeah hun I don't agree with culling but that's just me. I think all mice make great pets, all it takes is a bit of work. x
 
#6 ·
I can understand both view points when it comes to culling but I will state first that I do cull my litters down. For a few reasons.
In New Zealand, we don't have show mice, we don't have breeders who have been working on lines for years and years improving health. My main goal (other than type improvement) is to improve the overall health of mice. I've had far to many people coming to me to adopt a new mouse because their mice started growing very aggressive tumors at very young ages, or pass away before year.
I will cull runts because I don't want to be adding to the population of already poorly mice we have in New Zealand. Though in saying that, if there is a runt, I will give it a few days to see if it catches up to its brothers and sisters - if its weight gain is as constant as the siblings then I will give it a chance. If its weight gain slows or drops, then yes, I feel the best choice is to cull it.
 
#7 ·
Miceandmore64 said:
To be honest in my opinoun and dont even bother replying to change my mind. I breed on a tiny scale I have 1-2 male at a time and about 5 females. I breed one litter every month or 2. I also have 3 old does at the moment that are almost 2 and they are still here with me and ai am not planning on culling them.

About the if you don't have a use for something kill it. I would just give it away as a pet to someone who will let it live a life instead of being selfish and killing it because of your needs
it's not to do with being selfish Most breeders use there culled mice, they don't just kill them and throw them out. Most of mine who are no use to me but perfectly healthy are killed then frozen and later used for snake food. The mouse had a good life, a quick end and its body sustains another life. The mass produced frozen mice you can buy in shops are so small and thin compaired to my mice, my mice will make a better meal for the snake and will have had a better life. Some of the bulk frozen mice at work are covered in dirt and feaces I can only imagin the horrible condition they lived in.

Mice are not popular pets, and giving away old x breeding mice to pet homes is not allways practical, they may only live a few months then die on the new owner who is left deverstated the new pet has died so soon.

If you don't breed a lot you have the room to keep old mice there whole life, but if your breeding for a purpose that requires you to breed more often you don't have that space.

Everyone is entitled to there opyion but you should be respectful towards others even if they do not share your opinions them rather than generalizing and being insulting towards them.
 
#8 ·
Perluna said:
Thanks for the reply, that's all the information I wanted to know. Could you tell me how to spot signs of illness? For example, how would I tell a mouse that is weaker than its siblings if they all look the same?
In babies you may see them losing weight every day, after two days they can look like living skeletons. You can also see stunted growth, poor coats, and deformities, older babies can be also hunched up, get sick easerly, shuffle as they walk just to name a few I can think of to indicate weaker mice.

fizzle has summed up culling for me. humans chose to keep and breed animals they should be responsible for making sure there animals don't suffer and weather that means providing care, treating sick mice or culling quickly so be it.
 
#9 ·
Thanks everyone for all the information. I see it from both points of view - I understand the reasons behind culling and how it helps future mice yet I can't feel a pang of sympathy for the little ones who don't make it. I just feel fortunate to have a nice, chunky litter, despite there being so many of them!
 
#10 ·
Frizzle said:
The ideology of rat breeders is much different from mouse breeders, I would generalize that it is about "saving" animals and promoting rescues rather then improving a variety. I totally disagree with letting nature run it's course on domesticated animals that are clearly suffering.
And this is why I am no longer a part of any rat forum. If only there were a rat forum like this mouse forum. Rats would benefit a lot from more people culling and breeding for health.. maybe then a female rat wouldn't have a 70 to 80% (I forget the exact percentage) chance of developing a tumor in her lifetime.
 
#11 ·
Though I don't breed I would like to add that some reptiles need to eat pinkie mice.

They aren't big enough to eat older mice so they need pinkie sized. So some babies have to be culled to make food for reptiles.

So if a breeder knows they don't need any bucks for their breeding program they can instead cull the bucks and use the pinkies for snake food. This way the babies won't be going to waste.

I don't like culling and the babies just being tossed in the trash. The bodies should either be fed to animals that need them to survive or be buried an allowed to help something grow. Instead of rotting in a landfill.
 
#12 ·
Its unheard of and unpopular in the rat area to cull, but when I was breeding rats I would still cull. Even my largest female was not able to handle a littler of 17 little ones. Its sadly still frowned upon, but I was not willing to see mum or the babies suffer.
 
#13 ·
Much has been said already of the pros and cons of culling but one important factor has not been mentioned is the Animal Act which makes it illegal for us as humans supposedly of superior intelligence to allow an animal to suffer in our care. So above all we have a legal duty to prevent suffering. Grey area as to what suffering is.

Does bring up litters is stressful and exhausting to them depleting nutrients form their system to pass onto their young, at times this can be done to such a great extent that it makes the her very weak and as such would cause both the does death and the offspring. In the wild nature takes its course with predatory animals to some extent keep the population down.

Culling mice in captivity is doing natures work but more selectively as we can cull not only the weaker ones much earlier but also cull to prevent prolonged suffering. Selective breeding in captivity takes up alot of space and as has been said all culls are not wasted but will be used further up the food chain as in reptiles for those that keep or even birds of prey to others.

I agree with PPVallhunds that the frozen mice available from pet food stores do appear at times to be dirty and the conditions they are kept in may be brought into question. I also breed mice for the pet trade but hopefully I am providing much better quality of life not only for the breeders themselves as I treat them just as I do my pet lines and show stock never over breeding but also think of the animal they are going to be fed on and supply extra vitamins and minerals in the food and water throughout the life. Accurate record keeping will determine if a mouse I kill will be suitable to enter the frozen food chain as I have a policy that if a sick animal is to be culled it will not enter the frozen food chain.

Breeding for the show bench again requires space and the health of the mice to be at their best does bringing up litters will undoubtedly cause the animal to not be in the peak of condition due to feeding the babies and to prevent major loss of that condition culling is done to take out the weak and possibly sex also at an early age which not only prevents suffering of the doe from culling naturally not a pretty sight but ensures the best of the litter in the eyes of the breeder is kept to produce better mice in the future.

As for rat breeders saying they do not cull, I doubt that very much they just do not admit they do it, rats have large litters also and whilst more adapted to raising of such unless culling is done especially show stock lines then the same can be said as for mice quality will be lost with raising such large litters. Runts of the litters may die a slow and painful death so if no culling is done in the rat faternity and litters have runts then those allowing the runts to die in such a manner are in breach of the animal act. Unlike mice the male rats can be re homed much easier so culling down by sex is not as tough as for mice.

Nobody I think enjoys culling of any animal but is something that has to be done with captive bred animals to prevent prolonged suffering as the wild counter part. Hand raising is a difficult process and time consuming one and no guarantee of 100 per cent success rate to bring the baby up to full heath as with mice there is no milk substitute specifically for them like dog cat or other larger animals so doing so how does one know that besides keeping the baby alive and raising it to maturity that one has not also caused an impact on its natural immune system which would have been passed by the mother in her milk. It is only with individual accurate record keeping of quantity fed and weight that one will be able to detect if the baby will actually have a chance at survival and feeding every couple of hours round the clock for any single person has to be admired. Having a few people share the duties makes the task more bearable especially if one has full time employment also,

Each mouse is an individual and it is only through observation that owners are able to make decisions as to the size of litter that a doe can handle without putting the does life at risk in raising a large litter and the potential of her self culling causing suffering to newborns or even older babies.

To breed we must be both selective and responsible and look at many factors and not just breed for the sake of breeding, there are plenty of unwanted animals in rescue centres around the world that need good homes.
 
#15 ·
To add to what others have said about what happens when a female mouse culls her young on her own...I've personally witnessed that happen, at a pet store I once worked at. It was horrifying, and I never want that to happen again. Whenever possible, I try to cull my litters down within the first three days. The sole exception being when I'm test-breeding and I really need the additional data from letting a few more stay, at least until their colors come in enough to give me the information I need on their parents' genetics. Even then, I try to keep to an absolute maximum of 6-7.

The last doe I bred had NINETEEN babies! No way would a random pet store mouse be able to care for all of that on her own! I ended up having to go through and sort them first by who had the best milk bellies, and over half of them were already falling behind, and that was on the very first day, so it shows just how quickly a large litter can go downhill.

I don't usually cull adult mice, but when I do, it's for one of two reasons:

1. They are sick, and I can't afford to take them to a vet to be euthanized there. These ones can't be fed to a reptile due to their illness, so instead they get a stick of incense lit for them, they get wrapped up in a nice piece of leftover sewing fabric, and then I find a nice spot out in the woods to bury them.

2. They are caught routinely harassing other mice or culling babies for no apparent reason (which means I've checked their food and water, the babies appeared healthy or were well past the normal age for culling, or the babies weren't even their's to begin with). Between my friend and I, we've sadly had at least three who had to be culled for this reason; all three had developed a nasty habit of bullying other mice to the point of death (they had formed some sort of mouse gang in order to do this, which is why all three had to be culled), and they seemed to target younger mice in particular. They even viciously beat a doe who had just given birth, then stole all of her babies (and beat her again when she tried to take them back) and started culling them before we managed to get in there and save the rest (giving them back to their mother, in a separate cage). It started off as my friend's amateur temperament experiment with her African Soft-Furs: "If I harvest the meanest, most hostile ones as snake food and only leave the nicest ones to breed, what happens over the successive generations?"

So now that same rule has been applied to the fancy mice lines, and it not only prevents aggressive behaviors from spreading (either through genetic temperament or through the bullies traumatizing younger mice into following their example), but it's honestly not fair to the rest of the mouse colony to have to deal with constantly being abused and bullied.
 
#16 ·
I have also breed rats before and culled sometims its needed and important. I also agree with reptiles sometimes needing pinkies. Some will also not eat frozen thawed. Its not far for them just to die because the need to eat live....BUT if you start them off on frozen thawed from the beginning they don't get picky. Knowledge from working at a Vrt Hospital for 8 yrs and much rodent and reptile knowledge obtainwd from Vet Tech school