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  • 03-12-2014, 05:25 PM
    Michelle.C
    Pearl andPearl Merle Rats - Info/Picture Thread
    So many people have showed interested in Pearl Merles lately, thought I'd post an info/picture thread.

    http://i275.photobucket.com/albums/j...ps453b146b.jpg

    Question: What are the genetics behind Pearl Merles?

    Answer: Merle is linked to any Mink based rat. However, it stands out the best on Pearl. Pearl is also Mink based. Both UK and American Mink can be Pearl Merle, but American Mink has the darkest splotches. Pearl can be varying shades depending on the penetrance (how much the gene is coming through).

    Question: How do I produce them?

    Answer: You need the Pearl and Merle genetics to produce Pearl Merles. While not extremely rare, they can be difficult to get under a breeding contract.

    Question: Are Pearl Merle rats like dogs?

    Answer: No, they are not the same genetics seen in dogs. Double Dilution Merle in dogs can cause health problems, with rats, there are no health related issues in Pearl Merle rats. That said, homozygous (two copies) of Pearl is lethal in utero.

    Question: What is the difference between UK Mink and American Mink?

    Answer: They can look quite similar, but are genetically quite different. UK Mink is generally lighter (but not always) in it's original form. It also dilutes less when combined with other dilutions. In other words, where American Mink x American Blue makes Platinum, UK Mink x American Blue makes a black eyed Lavender. Much darker, but similar shade. American Mink is better for Pearl and Pearl Merle based lines though.

    Question: I have Pearl Merles, how do I breed for nicer Merles?

    Answer: Remove all other dilutions (Russian Blue, American Blue, c-locus, etc) as the combination of dilutes makes for very poor Merles. Also, select for a darker shade of Mink and lighter shade of Pearl when choosing your breeding stock. Because remember this, the splotches are NOT black. They are whatever shade of Mink you are working with.

    Question: So what rats can be Merle?

    Answer: All Mink based. Cinnamon Pearl Merle, Pearl Merle, Platinum Merle, Platinum Pearl Merle, Russian Cinnamon Merle, Russian Cinnamon Pearl Merle, Cinnamon Merle, Mink Merle, etc.

    If you have any other questions, feel free to post on this thread and feel free to contribute if you have Pearl Merles yourself. Picture spam now! :)
  • 03-12-2014, 05:27 PM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Roan Merles
    http://i275.photobucket.com/albums/j...ps3b5dcb06.jpg

    Rex Merle
    http://i275.photobucket.com/albums/j...ps99d70846.jpg

    Harley (long haired) Merle
    http://i275.photobucket.com/albums/j...ps4bdaca4b.jpg

    Light Phased Pearl Merle
    http://i275.photobucket.com/albums/j...ps25d9a8d0.jpg

    In these three photos there are Roan Merles (the blazed guys), Rex Merles, Light Phase Pearl Rexes, Harley (long haired) Pearl Merle and a Mink Merle.
    http://i275.photobucket.com/albums/j...ps453b146b.jpg

    http://i275.photobucket.com/albums/j...ps2b445a15.jpg

    http://i275.photobucket.com/albums/j...ps9238f63b.jpg

    Comparison between a Dark Phase Pearl Merle (bottom) and Light Phase Pearl Merle (top).
    http://i275.photobucket.com/albums/j...ps91fd3639.jpg

    http://i275.photobucket.com/albums/j...ps996985cf.jpg

    http://i275.photobucket.com/albums/j...psf8a2c16d.jpg

    Same Light Phase Pearl Merle as an adult.
    http://i275.photobucket.com/albums/j...psa5b690c0.jpg

    http://i275.photobucket.com/albums/j...ps4298b7da.jpg

    http://i275.photobucket.com/albums/j...psead30b3a.jpg

    Light Phase Pearl Merle Hooded Doe.
    http://i275.photobucket.com/albums/j...ps50759e34.jpg

    Light Phase Pearl Merle Hooded Buck.Hooded is not desireable as you lose splotches.
    http://i275.photobucket.com/albums/j...psd780dd7a.jpg

    UK Dark Phase Pearl Merles
    http://i275.photobucket.com/albums/j...ps603c18e6.jpg

    Light Phase (on the right) UK Pearl Merle. Splotches will be non-existant as an adult.
    http://i275.photobucket.com/albums/j...ps8c6b9f47.jpg

    UK Cinnamon Pearl Merle (center).
    http://i275.photobucket.com/albums/j...ps17f4539e.jpg

    Comparison - UK Mink baby in the front, American Mink baby in the back.
    http://i275.photobucket.com/albums/j...pse6dcf9b9.jpg

    Comparison - American Mink in the front, UK Mink in the rear. UK will get darker than this as an adult, but they are considerablly lighter (especially as juvies) than American, usually.
    http://i275.photobucket.com/albums/j...pse8ace95a.jpg
  • 03-12-2014, 08:34 PM
    MrLang
    Very nice! I work with merle myself but have not gotten them as nice as that. Thanks for the pics and info! I'll have some merle dwarves soon that I'm very excited about.
  • 03-12-2014, 09:16 PM
    sorraia
    I really want some merle.... You guys need to be closer so I can pick up a few!
  • 03-12-2014, 11:10 PM
    Rhasputin
    Would you agree that the Merle gene in rats (lets say Me/* for argument's sake) is dominant? Or would you say it's (me/me) recessive?

    It also sounds a bit like it's not so much 'merle', but splashed, like in mice. Splashed in mice is caused by a dominant gene (Spl/*) in addition to any c-dilution gene (ce c cch etc). It also shows up differently depending on the dilution level of the mice, which is similar to your 'light phase' and 'dark phase' merles. In mice, merle isn't really affected like that, and isn't connected to a dilution gene either. So if 'merle' in rats is connected to the dilution mink gene, would it be a stretch to say it's similar (if not identical) to the splashed gene in mice? Rather than calling it merle?

    Everyone is calling it merle, not just you, so it's not necessarily incorrect terminology (since everyone is doing it), but I feel like it's the wrong name for the gene personally.



    Edit: More info on splashed in mice. A splashed mouse is a diluted base colour with 'splashes' of colour that are not diluted. This is very similar to these rats.

    Here's some splashed mice:

    http://i1230.photobucket.com/albums/...B/DSCN4383.jpg

    http://www.thefunmouse.com/varieties...plashedlg2.jpg

    http://i196.photobucket.com/albums/a...1/CIMG8629.jpg
  • 03-12-2014, 11:17 PM
    Rhasputin
    Ahhhhh I don't want to nit pick (but I'm going to) but I think your (and maybe everyone's) terminology for 'roan' merle isn't quite right. Roan refers (as far as I know) to a mixture of white and coloured hairs (usually white and gray). Here is a merle mouse: http://www.eastcoastmice.org/im8iz6%20copy.jpg

    The gray mixed areas are the 'roan' areas.

    Here is a chocolate roan mouse: http://www.eastcoastmice.org/25owfly%20copy.jpg

    please inform me if I am wrong, but I don't think the ones you labled roan meet the criteria. I think technically (if my assumptions about 'merle' actually being splashed is correct) they would be TRICOLOUR RATS! :)
  • 03-12-2014, 11:57 PM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by Rhasputin View Post
    Ahhhhh I don't want to nit pick (but I'm going to) but I think your (and maybe everyone's) terminology for 'roan' merle isn't quite right. Roan refers (as far as I know) to a mixture of white and coloured hairs (usually white and gray). Here is a merle mouse: http://www.eastcoastmice.org/im8iz6%20copy.jpg

    The gray mixed areas are the 'roan' areas.

    Here is a chocolate roan mouse: http://www.eastcoastmice.org/25owfly%20copy.jpg

    please inform me if I am wrong, but I don't think the ones you labled roan meet the criteria. I think technically (if my assumptions about 'merle' actually being splashed is correct) they would be TRICOLOUR RATS! :)

    I'll answer your other post when I get home, but these guys are actual Recessive Roans. As in they gradually fade to white (unfortunately!). The breeder who had them before me mixed in UK Roans, American Blue, Harley, Satin, Dwarf and Manx (among other things). :) They do hold their color better than the actual Roan line I had though. But I really didn't want Roan in the Merle line, defeats the purpose. lol

    Roans in the rat world can eventually silver out all of the way and turn almost white, other lines hold their color better.

    Here is a three month old Roan Merle from that line. He's holding his color "meh", but I don't like the fact that the first thing to go is the spots! Makes me want to cry. lol
    https://scontent-a.xx.fbcdn.net/hpho...26865775_n.jpg
  • 03-13-2014, 12:02 AM
    MonkeyShuttle
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Awesome rats but everything else is too scientific. I can follow gray ones and brown ones :)
  • 03-13-2014, 12:16 AM
    Rhasputin
    Oh! So the 'roan' is technically a recessive gene separate from the dominant 'merle' gene? (that explains my confusion)
    I think in mice merle and roan are both recessives that are attached to one another. They act a lot like splashed, if splashed was recessive.
  • 03-13-2014, 12:32 AM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by Rhasputin View Post
    Would you agree that the Merle gene in rats (lets say Me/* for argument's sake) is dominant? Or would you say it's (me/me) recessive?

    It also sounds a bit like it's not so much 'merle', but splashed, like in mice. Splashed in mice is caused by a dominant gene (Spl/*) in addition to any c-dilution gene (ce c cch etc). It also shows up differently depending on the dilution level of the mice, which is similar to your 'light phase' and 'dark phase' merles. In mice, merle isn't really affected like that, and isn't connected to a dilution gene either. So if 'merle' in rats is connected to the dilution mink gene, would it be a stretch to say it's similar (if not identical) to the splashed gene in mice? Rather than calling it merle?

    Everyone is calling it merle, not just you, so it's not necessarily incorrect terminology (since everyone is doing it), but I feel like it's the wrong name for the gene personally.



    Edit: More info on splashed in mice. A splashed mouse is a diluted base colour with 'splashes' of colour that are not diluted. This is very similar to these rats.

    Here's some splashed mice:

    http://i1230.photobucket.com/albums/...B/DSCN4383.jpg

    http://www.thefunmouse.com/varieties...plashedlg2.jpg

    http://i196.photobucket.com/albums/a...1/CIMG8629.jpg

    I'm quite jealous that Merle mice are so much nicer (in general) than Merle Rats. Makes me want to get some mice. lol

    Pearl is lethal dominant, Merle is dominant (incomplete, I believe), in rats. It is not linked to the c-locus though, only to mm (Mink, both US and UK Mink can Merle).

    Light Phase/Dark Phase Pearl depends on how much the Pearl gene is able to express. Lighter the Pearl, nicer the Merle, imo. But Merle is in no way linked to Pearl.

    As I said in the original post, Merle in rats isn't the same as it is traditionally. I agree that it's not quite Merle, but the rat fancy has been calling them Merle since far before I started breeding. I own Blue Merle Rough Coat Collies, so..I can certainly wish the rats would looked like them (or mice). Then again, if I remember correctly, Merles aren't the same in mice as they are dogs. So, I guess rat breeders are just going on the "wishful thinking/hoping" route. lol
  • 03-13-2014, 12:36 AM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by Rhasputin View Post
    Oh! So the 'roan' is technically a recessive gene separate from the dominant 'merle' gene? (that explains my confusion)
    I think in mice merle and roan are both recessives that are attached to one another. They act a lot like splashed, if splashed was recessive.

    I'll just pull a copy/paste from NFRS about Roan Rats.

    "A strikingly marked bi-colour variety, with roan colouration, symmetry and contrast being important impressions. Clearly distinct from existing marked varieties. Roans are born solid coloured, but from the age of about 4-6 weeks they start to exhibit roaning.
    This is a steady increase in the amount of white hairs intermingled with the solid colour, starting with the face, sides and tail root on the juvenile, then working its way up to the nape of the neck with the moult. With each moult the rat becomes progressively lighter, the final effect not really complete until the rat is well into adulthood. The roan effect is most pronounced on the face, around the rump and the sides.
    Pattern: The Roan shall have as symmetrical markings as possible. The underside should be completely white.
    Head: A wide inverted V shaped blaze, including the whisker bed, coming as close to the eyes as possible without touching the eyes, and coming to a point between the ears. Jaw line and underside of the head must be white. Eye colour to conform to base colour standard.
    Body: From the head, the colour runs back covering the ears and continues along the body extending down the sides. Belly to be white.
    Tail: Unmarked tail preferred.
    Faults: White spots in coloured fur/ coloured spots in white fur. Brindled demarcation line. Lack of white on face and head or a completely white face or head.
    Genetics: Due to an unproven recessive gene not on the H locus with the amount of colour controlled by modifiers."
  • 03-13-2014, 12:41 AM
    sorraia
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    I wish roan rats were like roan horses, and held their color. Then I'd seriously consider roan rats.

    But seriously, I want some good merles. Mink is one of my favorite colors in rats, and the pearl and merle just make it better! Next thing I need are more chocolates.
  • 03-13-2014, 12:42 AM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by sorraia View Post
    I wish roan rats were like roan horses, and held their color. Then I'd seriously consider roan rats.

    But seriously, I want some good merles. Mink is one of my favorite colors in rats, and the pearl and merle just make it better! Next thing I need are more chocolates.

    Do you still have your Chocolates?
  • 03-13-2014, 12:45 AM
    sorraia
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by Michelle.C View Post
    Do you still have your Chocolates?

    Sadly no. :(
  • 03-13-2014, 01:08 AM
    Marrissa
    I want some fancy colored rats. Wish I could find some close-ish. I do have a mink female though.
  • 03-13-2014, 01:50 AM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by sorraia View Post
    Sadly no. :(

    You are Nicole of BWR, correct? I certainly wouldn't mind shipping out to you under a pet breeding contract.
  • 03-13-2014, 09:29 AM
    Rhasputin
    Here's an interesting gene in deer mice called 'ashy' that sounds very similar to the 'roan' gene in your rats.

    http://stkctr.biol.sc.edu/mutant-stock/ashy.html

    I feel like at the very least, the genes are misnamed merle and roan. I wish JAX would get their hands on some merle and roan and tell us what was really going on!! :P
  • 03-13-2014, 09:56 AM
    MrLang
    My light phase merles don't have nice spots as they grow like the dark phase ones. I can't tell what else I've got in there though. I tried to work it out with Nicole but my merles are from unknown lines and there seem to be other genes at play there.

    My question - do you think the rats that have higher expression of the dark spots pass that to the babies or is it totally random? I've been selecting for darker spots for a few generations and pretty sure they're only on top of mink, but they just don't get the way yours are there. Happy to share pictures etc. if you want to take some guesses on what I've got? Here are some pics of mine:

    https://imagizer.imageshack.us/v2/69.../imag0118c.jpg

    http://i30.photobucket.com/albums/c3...psc77b8d3c.jpg

    http://i30.photobucket.com/albums/c3...ps8c6d2a83.jpg

    This guy's sib expresses the merle much better than he does but he has some dark spots on him:
    http://i30.photobucket.com/albums/c3...ps8dd82b98.jpg
  • 03-13-2014, 10:41 AM
    sorraia
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Quote:

    Originally Posted by Michelle.C View Post
    You are Nicole of BWR, correct? I certainly wouldn't mind shipping out to you under a pet breeding contract.

    That would be me! Thank you for the offer to ship, that makes me super excited! With it being tax season and I had a recent surgery, I'll have save up some extra money for the shipping, but we can keep in touch and get it figured out. :)
  • 03-13-2014, 10:43 AM
    sorraia
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Goodness rhasputin, mice come in so many amazing colors! I wish they didn't smell so strong, I'd love to work with some of those. (I think I just have a really sensitive sense of smell, but I can't stand how mice smell. When we do mammal trapping at work, I know when its a mouse before I even open the trap, just by smell. Half the time I can even tell what species by the smell! Weasels too, they stink pretty bad. )
  • 03-13-2014, 10:53 AM
    Rhasputin
    :D

    I might be drawing false parallels between mice and rats, but I feel like something is going on in there with the rat merle gene. :P
  • 03-13-2014, 11:53 AM
    Wapadi
    I wish you guys could box up some of these guys and send them to me :please::please::please:!
    My collection is mainly hooded rats and Siamese rats. Sigh.....
  • 03-13-2014, 09:53 PM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Pearls, Pearl Merles, etc. can be a HUGE pain in the butt to get right. Out of all of my lines, I've had to work the hardest on getting the right shades with them. To be honest, it looks like you are working with UK Mink. They look the right shade and it could explain you not being able to get lighter Pearls while maintaining splotches. The second and third photos definitely lead me to believe this. The first photo is tricky because the darker babies don't match UK or US Pearls that I usually see. The lightest baby in the first photo could be Russian Pearl, which could also be lightening your splotches along with the base coat.

    My first suggestion would be to find an American Mink to out cross to. My guess is you'll see a few black bubs (meaning the guys you have are UK). Remember, American Mink produces (by far) the best Pearl Merles. Breed the off spring back together and you should start seeing some American Mink, American Mink Merle an American based Pearl Merles. From there, select towards the darkest splotches, lightest Pearls, darkest Minks. American Mink is relatively easy to find, but you might have to out cross to a black to try and weed out some of the other dilutes. ALL other dilutes are a negative thing in a Pearl Merle line. You only want the dilute of American Mink with the Pearl and Merle modifiers.

    The number of Splotches and Spots are completely random. But the shade of the Merling can be selected for. Just choose the darkest Splotches to carry on the next generation.

    So you are saying you think you only have Mink Merles? I disagree. You obviously have Pearl at play, it's just low penetrance. In my UK line, I had to out cross to get a lighter Pearls. But the most important thing for you to do is find an American Mink and work away from the lighter splotches.

    In the first photo I see very dark phase Pearls and the lightest baby looks either Double Mink Pearl (US Mink, UK Mink and Pearl) or Russian Pearl (Russian Blue, Mink and Pearl), depending on her eye color. An adult picture might tell me more though.

    In the second photo the light brown Merle baby looks UK Pearl Merle. The other Pearl baby looks either UK Pearl or Double Mink Pearl. It's hard to see the others. Is that a diluted Black or Mink on the left?

    Third photo is DEFINITELY UK Pearl Merle.

    Last photo also looks UK Pearl based.

    I'll post some various shades of UK Pearl below. Keep in mind that both American Mink and UK Mink is extremely variable, thus leading to a variability in the shade of Pearl you'll see. That doesn't even count possible further dilutions or unknown modifiers.



    Quote:

    Originally Posted by MrLang View Post
    My light phase merles don't have nice spots as they grow like the dark phase ones. I can't tell what else I've got in there though. I tried to work it out with Nicole but my merles are from unknown lines and there seem to be other genes at play there.

    My question - do you think the rats that have higher expression of the dark spots pass that to the babies or is it totally random? I've been selecting for darker spots for a few generations and pretty sure they're only on top of mink, but they just don't get the way yours are there. Happy to share pictures etc. if you want to take some guesses on what I've got? Here are some pics of mine:

    https://imagizer.imageshack.us/v2/69.../imag0118c.jpg

    http://i30.photobucket.com/albums/c3...psc77b8d3c.jpg

    http://i30.photobucket.com/albums/c3...ps8c6d2a83.jpg

    This guy's sib expresses the merle much better than he does but he has some dark spots on him
    http://i30.photobucket.com/albums/c3...ps8dd82b98.jpg

  • 03-13-2014, 09:59 PM
    Michelle.C
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Medium Phase UK Pearl, she carries American Mink though, so..I have gotten a few nice Pearl Merles out of her.
    http://i275.photobucket.com/albums/j...psaa7ade69.jpg

    Light Phase UK Pearl.
    http://i275.photobucket.com/albums/j...pscfabd0fb.jpg

    Low penetrance/Dark Phase UK Pearl, also a Harley.
    http://i275.photobucket.com/albums/j...psd86f5788.jpg

    UK Dark Phase Pearl, Harley.
    http://i275.photobucket.com/albums/j...ps5d5e5f2b.jpg

    UK Russian Pearl.
    http://i275.photobucket.com/albums/j...ps1faa1f22.jpg

    UK Dark Phase Pearl.
    http://i275.photobucket.com/albums/j...n/IMG_0714.jpg

    Believed to be a UK Dark Phase Pearl Merle.
    http://i275.photobucket.com/albums/j...s/IMG_2252.jpg

    Comparison - American Mink on the left, UK Pearl in the middle, UK Dark Phase Pearl on the right.
    http://i275.photobucket.com/albums/j...s/IMG_1283.jpg

    Undercoat of a Pearl. It should be cream/white.
    http://i275.photobucket.com/albums/j...n/IMG_0715.jpg
  • 03-14-2014, 07:44 AM
    ballpythonluvr
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    I don't know a damn thing about rat genetics but those are some of the prettiest and cutest little ratties I have ever seen. God, I love baby rats, they are just too cute!
  • 03-14-2014, 11:36 AM
    MrLang
    Wow thanks, going to look at what i've got and take some more pictures and get back to you!
  • 05-18-2016, 01:33 PM
    ALWE
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Hi Everyone,

    I hope you don't mind I resurrected this thread, there seems to be some experts on here and I am a little stumped!

    What color would you say momma rat is? This picture below doesn't show her true color (mom and babies are showing much darker here because of the shadow), but it does show the comparison between her color (very creamy) and her babies (more grey). She is mink based I would assume, she was bred to a mink merle male and has had 2 litters of all mink/pearl (?) babies, such as below.

    https://drive.google.com/open?id=0B4...ENmR1M2a2I4eVU


    This picture of momma below is more true to her color, very very pale almost to the point of being white.
    https://drive.google.com/open?id=0B4...3JpamtZMXNNam8

    And this picture below is of two of her boys, which is also showing more true to their color, very light grey with merle spots.
    https://drive.google.com/open?id=0B4...Xh0Qm40SWs3WDQ

    And this is dad, a mink merle. He is massive! :)
    https://drive.google.com/open?id=0B4...TZMYjBfQjhlMmM


    A little background - we responded to an add on kijiji a few months back from someone giving away baby rats (we keep them as pets). He had a litter, mom and dad all in the same cage and didn't seem to know too much about them at all (ie. how to tell male/female, when to separate, how fast they reproduce!). We took a female as planned, but also took the only 2 merle boys as well, as they were so striking. Interestingly (awkwardly?) he kept in touch with us, texting updates everytime momma got pregnant again. I guess it got way out of hand and he asked us this weekend if we would take mom and dad, he had had enough. We brought them home and in better light I realized that momma is such a beautiful and distinct color. I assumed her babies were pearl merle, but what color would she be? I am guessing we might be expecting a litter from her within the next few weeks, she was living with the male and weaned her last litter about 2 weeks ago.

    My pictures are not great yet, both mom and dad are still pretty shy. I can take more pics as they warm up to me though if that would help.

    Thanks for any insight!
  • 05-18-2016, 01:51 PM
    ALWE
    Re: Pearl andPearl Merle Rats - Info/Picture Thread
    Sorry, it looks like my pictures didn't post... lets try again.

    Mom and babies (all look darker than they actually are). Mom looks creamy/warm, while boys look grey/cool. Mink based.
    [IMG]http://i1152.photobucket.com/albums/...pswmyjadct.jpg[/IMG]
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