A little Concerned and curious...

[Mrs InsaneOne]

Ok, while I normally don't post much here in the feeder section and have never before now posted my own thread here, I have frequently browsed through here looking for answers or just reading up when the mood strikes me.

I've had my mice for nearly two years now (at least it seems that long to me) and I've been noticing some strange happenings with two of the colonies of mixed mice that I have. When I say mixed, I mean that I have two colonies that have both pink-eyed white mice, brown mice, black mice, and a spattering of 'ringed mice' (black or brown white white rings around their bellys)

I don't really know much about rodent genetics to tell the truth I don't particularly care for the little buggers (which is why I have no quams about feeding my snakes. *weg*). The mice in these colonies have come from three seperate blood lines as I don't feel all that comfortable inbreeding the critters too much. Yes, there were problems in the begining that led to a few of the mice dieing because of different strains of something that led to respitory illness - that had happened long before I knew better - but the surviving mice were stronger and thier litters were healthy so in the end it all worked out.

Yes, yes... please be patient. I am getting to the point. I just want to be a complete as possible in my explanation because it may prevent a flame later down the road as I've noticed people carrying torches around the forums lately.

ANYhow.. The original blood lines were pink eyed whites, solid browns, and solid black. It didn't take long for the 'ringed' mice to start showing up though, and I figured it to be a genetic trait that one or more of the mice were carrying. No big deal - those mice are healthy with no trouble at all. They actually end up getting slightly bigger then the all pink-eyed whites produced by my seperate p.e.w. colonies. Odd really...

But back to my point. Now that those ringed mice are producing thier own offspring (and in some cases I know some in-breeding is occuring because I can't keep all the little squirmy buggers straight because they all look so much alike) and every once in a while I will get black-eyed white mice with either dark brown patches or black patches popping out. Only about a handful that I am aware of over the last year and of those handful, only two have survived long enough to become hoppers. And no, it's not because I'm feeding them off (though I have some).

Usually though, these black/brown and white mice are eaten within a week of birth or shortly after reaching the fuzzy stage. I have always suspected it to be a genetic disfunction (not sure if that was the word I was looking for or not...) caused by something in the mouse genes. it is only the patched mice that develope kind of funny (Will post pictures to give a visual and will explain better in a bit.)

The first one that reached hopper stage died very suddenly when it seemed to be fine - though I always knew it wasn't going to live long. I didn't think much of it at the time because I thought it a one time fluke (more hoped it was a one time fluke). I did start making a mental note of each and every patch mouse born and tracked their progress just to see if it occured again because like I mentioned earlier, the baby patches were usually eaten before they got much bigger then fuzzy stage by the other mice.

After months of watching and taking notes - I finally have another hopper patch and it is developing the same way that the first one did. I don't know how to discribe it... they just look wrong. No, they don't have extra tails, feet, or eyes... they just look disproportionate. It almost looks like they have a tumor growing in thier tummies and they seem weaker then thier siblings and cousins.

I know it's not husbandry - because it never shows up in any of the other mice. ever. And I have grown out more mice, over the last two years, then I can count so I feel I can say that with confidence.

What I am interested in knowing... is if anyone else out there has run into a similar problem and if there is a solution other then never breeding those colonies again. I did do research. I didn't find anything similar which is why I am posting. Maybe I was just searching under the wrong terms, but I did search.

I have seen other, healthy, patched mice being sold as fancy mice in petstores and know there are others out there that breed them successfully - so it makes me wonder why my particular mice can't seem to thrive.

Any help, comments, or even genetic tutorials (remember the kiss method please - keep it simple stupid... the stupid being me and complex genetics! lol) would be greatly appreciated.

Now that I think I have bored you enough with my long winded explaination. I will post several (and by several I mean over a dozen) pics of the mouse (hopper patch), a sibling from the same litter, and some pics of younger siblings for comparason. I don't usually take many pictures of the mice. They are food for the critters and I try not to become attached or make anyone else attached to an animal that could end up as lunch tomorrow. But I wanted to give a clear picture of what it is that I am seeing.

Pics in next post...

Jenn

 

[Mrs InsaneOne]

These first three pics are of the one mouse all by her lonesome (Yes, it is a she and the previous patched mouse that lived to the hopper stage was male, so I know it's not sex related. Sorry, I forgot to state that earlier... my bad!)

In this first one, you can see a little of the way her tummy bulges out towards the back half of the mouse. It's not food, that lump is always there and has been steadily growing for about a week or more. I meant to keep written records, but it's been hard to find the time lately with everything else going on.

This next pic is from the back of the mouse, and doesn't really show the bulge real clear, but you can see that her rump and abdomin is larger (swollen???) then her front half.

This last picture shows it best. If she was older, I'd swear she was preggers, but I know for a fact she's not. Just isn't old enough and that lump/bulge is not as flexible as a woom full of babies is.

The pictures in the next post will be of the mouse with a sister from the same litter...

 

[Mrs InsaneOne]

There are several things in these pictures that I noticed right away as the two mice were being photographed.

1) The black mouse is larger.
2) The black mouse looks healthier.
3) The black mouse's eyes look brighter and are opened wider.
4) The fur of the black mouse is shinier, fuller, and slicked down where as the patched mouse looks kind of unkempt by comparison.

They are indeed both from the same litter as they are the oldest babies in the colony - two of five remaining litter mates after their brothers and sisters were up... relocated... well fed off really.

Here are a few more of those same two mice with one of their younger siblings:

More in the next post...

 

[Mrs InsaneOne]

These last handful of pictures are of the two younger siblings from a later litter together. I don't know if they are from the same litter or not - I had three litters all born with 2-3 days of each other and it's hard to keep track of which pink came from which mother when they all whelp that close together. I wasn't able to find any black or brown mice to compare with these two, because all the mice were getting all worked up and my daughter was getting tired of holding them. I will try to get some shots of the rest of the young pinks and near fuzzies later. (If any one thinks they are truly needed.)

Next I have a close up of each of those same two mouse by themselves.

That's the last of the pics I took tonight... well last night now. I do have younger pinks in another colony that appear to be patched - but I didn't want to distrub the new mother in that tank and frighten her into eating any of the babies. I will try to get some pics when we clean out cages again tomorrow.

Again, any info or comments is welcome!

Thanks in advance
Jenn

 

[diamondlil]

There certainly does look to be a visible difference in the mice, apart from the enlarged abdomen, the smaller eye is clearly seen. Being curious, personally I'd kill a deformed and normal mouse of the same size, and do some dissecting to compare size of liver etc.
I'd be inclined too, to cull out that line of mice, just because they aren't going to be as productive in the long run as mice that don't produce deformed offspring.

 

[Mrs InsaneOne]

There certainly does look to be a visible difference in the mice, apart from the enlarged abdomen, the smaller eye is clearly seen. Being curious, personally I'd kill a deformed and normal mouse of the same size, and do some dissecting to compare size of liver etc.
I'd be inclined too, to cull out that line of mice, just because they aren't going to be as productive in the long run as mice that don't produce deformed offspring.

I've considered the dissection and if my oldest was two years older I'd turn it into a science project for her and a real learning experience. But I just don't have the room, tools, or um.. what's the word I'm looking for? Ah... desire.. maybe... I just never liked cutting apart animals though I did do the frog and worm dissections in biology class in high school.

As far as the culling - nature (for the most part) has been taking care of that itself. Though some have for sure been fed off to the snakes. I hate the thought of completely dumping two entire colonies to prevent that 1 in 20 or 1 in 30 deformed patch. But, as those colonies age, I am seriously thinking about not using thier off-spring to start new colonies. I have six or seven other, healthy colonies (of PEWs) that I can take future breeders from.

It's hard to juggle and balance though. I raise the mice as food - not pets, and I don't think the snakes really care what color thier mice are (except the one BP that we sold who would ONLY take colored mice - the reason we started breeding them in the first place!) So as long as I can cut back the colony while still producing enough mice to feed the growing brood (it will NOT pass 80 this year... as long as we don't include any off-spring we produce! lol) . That's the only reason I hesitate to just drop the two colonies at the drop of a hat. Though the thought has crossed my mind.

Thanks for the input!

Jenn

 

[diamondlil]

When I used to breed gerbils I had one pair who used to cull out of their litters, I didn't know why until they let a baby grow who definately had neurological problems, hence 'Twitch', who used to have fits but was otherwse healthy, lived as a pet and I stopped breeding the parents so as not to carry those genes on. (The parents were totally unrelated as far as I knew, bought from different sources, so it was just genetic bad luck)

 

[diamondlil]

(and as gruesome as it may seem, dissection was my favorite part of biology!)

 

[Mrs InsaneOne]

(and as gruesome as it may seem, dissection was my favorite part of biology!)

It would have been mine too, but I couldn't get the image of Kermit the frog out of my head as I stared down at the limp frog that was secured to them little black trays... I kept hearing Miss Piggy screaming in the background that I killed her husband... :eek1:


The more I think about it though, the more I'm thinking of just slowly phasing those two colonies out. IE not supplying new females and not starting new colonies from thier off-spring. They are such cute little things and Tim just loves the wide banded ringos that we get out of both cages - but it's not a gene I want floating around in my pool if I want to keep these guys going without adding new blood and the new fear that I'll lose more mice to the bacteria? Parasites? Other thing that causes some mice to get RI's because they all carry different ones thing? Am I making any sense?

I think I need to go to bed and clear my mind after reading that Mean Adult Corn thread that sent me into a giggleing fit worthy of a high school drama queen meeting her favorite male actor for the first time just before falling falt on her face.

Thanks again!

Jenn :crazy02:

 

[diamondlil]

Have you tried the 'virtual frog dissection'? I haven't got the link but it's on an excellent website

 

[Ssthisto]

White spotting patterns can often cause problems in mice - some of them are lethal homozygous genes that hit the mice before they're born (the embryos are reabsorbed) and some of them are semilethal.

Eva's Mouse Page has this to say about marked mice:

Piebald (s). This gene is responsible for Dutch, Even, Broken and and partly for Dark Eyed White. These animals, not only having spots of no pigment in the fur, also may have spots of no pigment internally. Furthermore, the gene s is also associated with megacolon. As many as 10% of the ss mice might die from this disease. Megacolon in ss mice is associated with a marked reduktion of myenteric ganglion cells. When the mouse gets sick the colon gets distended and filled with fecal matter. There is no cure to this disease.

That sounds almost exactly like what's happening to your patched mice - that they're piebald-gene babies, and that they just happen to be hitting the 'bad' side of the piebald gene.

This is one reason why I try to breed solids rather than marked mice.

 

[Mrs InsaneOne]

Have you tried the 'virtual frog dissection'? I haven't got the link but it's on an excellent website

Shudders.. are you trying to give me nightmares??? lol J/K.. if you find the link I'd be interested as I need to prepare my oldest for when she starts dissection in a year or two or three... depends on how the homeschooling goes. If it is on a pre-killed animal I wouldn't have as much of gag reflex gross-out spell as if I had to do it on a feshly - OMG I had to kill it myself type of thing...

White spotting patterns can often cause problems in mice - some of them are lethal homozygous genes that hit the mice before they're born (the embryos are reabsorbed) and some of them are semilethal.

Eva's Mouse Page has this to say about marked mice:

Piebald (s). This gene is responsible for Dutch, Even, Broken and and partly for Dark Eyed White. These animals, not only having spots of no pigment in the fur, also may have spots of no pigment internally. Furthermore, the gene s is also associated with megacolon. As many as 10% of the ss mice might die from this disease. Megacolon in ss mice is associated with a marked reduktion of myenteric ganglion cells. When the mouse gets sick the colon gets distended and filled with fecal matter. There is no cure to this disease.

That sounds almost exactly like what's happening to your patched mice - that they're piebald-gene babies, and that they just happen to be hitting the 'bad' side of the piebald gene.

This is one reason why I try to breed solids rather than marked mice.

Thank you so much for the info, input and link! It does sound very like what is happening to my mice becaue they sure seem to start off normal enough looking. Poor things. If that is indeed the case and further reading when I am more awake will help with a possible trip to the vet with this hopper I have will determine on how I deal with the two colonies.

I have no trouble feeding off the patched/piebald babies as pinks to insure they don't suffer as I phase out the colonies. I'm just glad I'm breeding for feeders and not for the fancy colors. I think the mice are neat - I have a black one with a white star on her belly... but I don't feel right knowing that a baby born would grow to adulthood or in this case to hopper size suffering. Best to stop it all together!

Thank you again!

Jenn

 

[Flagg]

From the description I was also going to mention megacolon and the dominant spotting gene.

Nothing much you can do to avoid it besides not breeding those mice that produce them.

 

[cassandra]

From the description I was also going to mention megacolon and the dominant spotting gene.

Nothing much you can do to avoid it besides not breeding those mice that produce them.

I was gonna say megacolon as well...but I know nothing more about it. =P

 

[Mrs InsaneOne]

Thanks Flagg and Cassandra... I spent about 3 more hours researching the whole piebald mice thing last night and found a few pictures and I believe that is what it was as well. Unfortunately, that pied hopper didn't last the night as we found him dead just a short while ago. Just as well, the little thing would have been suffering from what I read last night.

The younger pied pictured will be fed off immediately, as will all future pied offspring and I'm going to start the process of weeding out the genetics of the line. I may get flamed for this, but I can't afford to just stop both colonies right now. They are actually the largest producing colonies I have - yeilding twice as many pinks as my PEWs do.

None of the healthy mice will leave this house unless it is in the belly of a snake - so I don't feel as guilty about letting the colonies continue on for a short while longer. So there is no chance that a carrier of the gene will end up in someone else's mice colony due to my mice.

Thanks again for all the input and comments!

Jenn

 

[diamondlil]

That's incredible, who'd have ever thought a coat colour/pattern would have such implications? I can't see any reason you'd be flamed over this at all. You've used resources to find out the reasons behind an anomaly in your colonies and are going to take steps to ensure that the particular strain associated doesn't reproduce itself.

 

[Flagg]

Not sure if it's the same gene, but I occasionally get spotted mice in my colonies, and they always die young. No megacolon, but for some reason they just don't ever make it.

I've got 1 spotted male right now that seems to be ok so far, I've started him in a colony with 2 PEW females. No production yet but its still relatively early.

I started out with a lot of different colors but now for some reason all I have is PEWs and solid black or grey mice. So I'm giving this spotted guy a shot.

 

[sfaoldguy]

The pet store I sell my extra mice to had about 30 of those blotched mice they got from a supplier. All of them looked weak and sickly to me. I brought two of them home to test out their genetics with my normal mice. One of them died the first week or so. They were both females put in with an established male and another female. They did fine for a week and then I found the one pretty much dead and it had injuries. The other one is still doing well and seems to be getting healthier. I have not noticed anything like twitching and it is growing nicely.

 

[gumdrop]

How fascinating!! well, I think I will just stick with plain old boring PEWs. They are only food after all. It is all very interesting though.

 

[Ssthisto]

Not sure if it's the same gene, but I occasionally get spotted mice in my colonies, and they always die young. No megacolon, but for some reason they just don't ever make it.

I've got 1 spotted male right now that seems to be ok so far, I've started him in a colony with 2 PEW females. No production yet but its still relatively early.

I started out with a lot of different colors but now for some reason all I have is PEWs and solid black or grey mice. So I'm giving this spotted guy a shot.

Could be dominant White - which is a homozygous lethal. You can get SOME spotties that are fine (heterozygotes) but homozygous animals do die young.

Most of the spotted genes do carry problems - it's because the pigments in skin have other implications for unpigmented internals - it does affect their functioning.