Spotted White rabbits, Megacolon.

squidpop · Jun 4, 2014

I'm wondering if anyone knows:
In the case of true charlie rabbits: defined as rabbits that have two genes for spots EnEn, which causes them to be almost completely white with only little spots of black around eyes and ears, but mostly white
What is the chance of Megacolin? Is there a 100% chance, or a 50% chance? Do all charlies have megacolon?

OakRidgeRabbits · Jun 4, 2014

I don't know that the genes that cause charlie coat patterns are linked to megacolon. I've had a number of charlies, and they have all been healthy.

squidpop · Jun 4, 2014

That's good to hear. That does help answer my question. But do you know if they are true charlies or false charlies?

It is known to be linked to the English spot gene though— En En. On this link first line of paper says, "The Megacolon-Syndrome is a hereditary disease of homozgous spoted rabbits (En En)." http://www.medirabbit.com/EN/GI_diseases/Mechanical_diseases/megacolon.pdf

Also,
http://truluvrabbitry.com/2012/06/03/charlie-megacolon/
https://www.flickr.com/groups/bunnyloversunite/discuss/72157637410954374/

I haven't run into anyone who's rabbit has megacolin and isn't a charlie... yet, all the ones I've seen are charlies.

But sometimes rabbit can be false charlies En en. Also, some charlies are En en and have a dutch gene that causes the extra white.

Azerane · Jun 4, 2014

I can't remember who it was on here, someone had a rabbit who had/has megacolon, but for the life of me I can't remember. I'm sure there have to rabbits that have megacolon and aren't charlies.

Hard to be sure about how much of a risk it is without knowing the exact parentage of each rabbit to determine whether it is a true or false charlie.

JBun · Jun 4, 2014

My dwarf hotot Toby, has megacolon, though at this point it is a pretty mild case controlled well with diet. Not sure there is really any data like what you are looking for, as not much seems to have been studied in regards to this. But just speaking for my buns, out of 9 dwarf hotots, 7 of which are/were white with black bands or no bands, two have/had megacolon, and one other possibly may have had it(or something with similar symptoms), though I believe his developed from prolonged GI issues, though I'm not sure about this.

Most of the buns that I have read about with megacolon, have been charlies, but I do recall reading of one that wasn't.

squidpop · Jun 5, 2014

Thanks everyone for replying. It sounds like megacolon isn't as common as I feared. I think since my charlie has it I was thinking they all did.

I emailed the house rabbit society and got this reply from Ph.D. Dana Krempel.

Not all "charlies" have the congenital failure of their melanocyte neuron-precursor cells to properly migrate and innervate the gut. It's a polygenic condition, and also possibly influenced by in utero environment. In short, the actual developmental mechanism isn't fully understood.

I would say the vast majority of "charlie" rabbits do NOT have the condition, though. It's not all that common. But it's awful when it does show up.

Dana

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Dana Krempels, Ph.D. ^
Senior Lecturer, Director of Undergraduate Studies ^
University of Miami Department of Biology ^
[email protected] ^
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Compassion towards animals is essentially ^
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