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Post by legendrockranch on Oct 22, 2012 22:37:17 GMT -5
E+ doesn't always give you mealy noses or dark reds. You can have regular coloured hair at the nose, and bright red bodies, too. I believe you only get the black nose or spotted nose with E+; pink noses are e. This has been my experience, E+ animals black noses or spotted noses, pink noses are e. As far as the mealy muzzle ring, sometimes as the animal ages it disappears. So I agree with you c.
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Post by marion on Oct 23, 2012 9:19:24 GMT -5
Excerpt from an old email, from a breeder with a large herd of mostly reds: "A wild-type can be very carrot red/pink if they don't have other shading genes to mix in a lot of black pigment. A homo true-red is always pink nosed."
ps: In context, I was asking him about a particular cow I owned, so it didnt include discussion as to whether an e/e red/pink cow could have nose spots.
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Post by midhilldexters on Oct 23, 2012 13:13:15 GMT -5
Hi Marion,
;D It wouldn't surprise me if your email was from the same guy that owned the 3 animals that I posted pics of !! He certainly realized by 2011 that some e/e animals could show speckled noses as evidenced by his own herd.
Carol
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Post by legendrockranch on Oct 23, 2012 14:18:38 GMT -5
I was just reminded by a fellow breeder of an e-mail that I received last year from John P. reguarding this matter.
Below are his observations....
"Here is some information you may find helpful:
1. I know that e/e cattle aren't supposed to be able to have or show any black pigment, but I have seen and/or owned plenty of e/e animals that do show black pigment. The 3 animals whose pix are attached are MLW Chamomile 14588, SGF SBAN Saber 018869, and SGF LPFK Titan 13963. All 3 are e/e reds. The black pigment in Saber and Titan is confined to the speckles on their noses. Chamomile not only has a black-speckled nose, but also she has a black muzzle ring, black hair inside her ears, and black in the switch of her tail.
2. Dexters that are e/e may have pink or speckled noses. I have not seen any e/e Dexters with black noses.
3. Dexters that are E+/E+ or E+/e may have black, speckled, or pink noses.
4. Red (E+/E+, E+/e, or e/e) Dexters that are homozygous for dun (b/b) have pink noses, not speckled and not black".
Patti, if your reading this do you care to comment? This might be one of those things we'll never have an answer to.
Barb
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Post by cddexter on Oct 23, 2012 16:08:43 GMT -5
Barb, I think John has had more experience than anyone. He also is the only one of us with the genetics background to make more or less definitive statements. I know that Jaynes' reds were little e, some were heavily blackfaced, etc. but all had pink noses. I'm pretty sure she didn't have dun, even if just hetero, so her pink noses must have been different genetics from John's. So it seems to come down to what each of us has seen, or been exposed to that forms our opinions. That's certainly true in my case, it seems to be in yours, too , and from the posts, from the AU poster as well. I'd take John over all of us. Mind you, havng said that, perhaps if someone (like Patti?) wanted to take the time to do some research into backgrounds, maybe we'd find there are specific lines that carry specific modifiers. That would account for why some have one experience, some another...it all depended on what genetics were around in the individual herds. cheers, c.
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Post by midhilldexters on Oct 23, 2012 18:39:57 GMT -5
I certainly would have agreed with CD, Barb and Marion had I not seen those pics I posted. All the e/e animals I have seen have had pink noses. It really is fun to learn that there is just more to it than we all thought, and makes me wonder what else will crop up to amaze us next time.
Carol K
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Post by lindonestate on Oct 24, 2012 22:30:31 GMT -5
Colour testing is the only way to know for absolute that an animal would be E+ or e. Its only an assumption going by the majority that E+ would display some black pigments and e would only be red with pink noses.
It really isnt any differrent to the short legs are definite chondro carriers and long legs are not - we all know this isnt true, but was based on the 'majority'
Thank goodness for genetic testing being (cheaply) available. In 10 years time there will be new tests, efficient tests and current tests which provide more information than they do today.
Gotta love the 21st Century.
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Post by cddexter on Oct 24, 2012 23:29:55 GMT -5
umm, lindonestate...don't want to hijack the thread...but by definition, 'shortleg' is hetero chondro, and 'longleg' is a non-carrier. If you mean there are sometimes a few animals that are hard to tell, well okay. Otherwise, shorts are carriers and longs are not. What did you mean? cheers, c.
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Post by cddexter on Oct 25, 2012 10:50:09 GMT -5
lindonestate...are you Lindsay or Donna? Nice area you live in. I went from Wagga to Melbourne by bus (Ellen Howes to Liz Williams) and the countryside was beautiful. Thanks to my Dexter friends, I've been all over QLD, NSW and VIC, as well as WA and TAS. What I appreciated most was the combination of English politeness and American we can do it attitude. Great country. Yes, we are very lucky to have dna stuff to go by now. E+ was identified as present and red in '97 (me), dun and chondro loci published in 2002 (Sheila Schmutz with John Potter, and Julie Cavanagh), and pha in 2008/9 (Jon Beever). It would be nice to think some of the more esoteric cosmetic traits will one day be identified, but I'm not going to hold my breath. Functional and production traits trump cosmetic traits in new dna research. Darn. cheers, carol d.
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Post by Cascade Meadows Farm - Kirk on Oct 26, 2012 21:06:46 GMT -5
Dun (Brown) is NOT considered to be a "dilution" of black, but rather is an incomplete black (that looks brown).
There are only two pigments found in most all mammals.
Eumelanin = Black Pigment Pheomelanin = Red Pigment
Many genes impact how and where these pigments are produced in animals.
Dun (brown) is Eumelanin (black pigment).
In producing the color BLACK, there are a series of chemical steps required to complete the production of eumelanin. The final step catalyzes the pigment, forming a good quality black color.
A good working gene/protein (tyrp1) is required to complete the successful formation of the black pigment. The good working gene (B) is dominant to the broken mutant gene (b) which is recessive. The good working dominant gene can override a recessive broken mutant gene and can complete the formation of the color black. So you only need one good gene (B) to finish the job of producing eumelanin (black).
But if there is no good working gene present, and there are two broken genes (b/b), then the animal is unable to complete the final step in producing eumelanin, and so the unfinished pigment appears brown, instead of black.
Dun (Brown) is not typically referred to as "Diluted Black" because there are other genes that can actually dilute black but they create a blue/gray look (and not brown). There is actually a gene locus for "Dilute" in some breeds of cattle, but that has nothing to do with Dun (Brown) in dexters.
So a Dun Dexter is really a dexter that wants to be black, but with two broken genes that make it unable to finish the job of producing black pigment, and so the unfinished eumelanin looks brown.
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Post by cddexter on Oct 26, 2012 21:40:42 GMT -5
Oh my goodness. Hi!!!!
long time no hear. Great to see you posting again. hope all is peachy keen in your neck of the woods. best regards, carol d.
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Post by Cascade Meadows Farm - Kirk on Oct 27, 2012 10:08:24 GMT -5
Here's why e/e reds can have darkish noses and some black hairs on very limited parts of their bodies. Also, here's why the color dun (brown) , can appear on e/e reds and E+ reds: Mammals, including dexters, only have 2 pigments Eumelanin = Black pigment Pheomelanin = Red pigment As previously discussed, Dun is simply unfinished black (eumelanin) pigment. There is no such thing as dun pigment. Many genes at various locations impact the two pigments The Extension locus (a holder of gene alleles) is a primary controller of black and red pigment E+ = the ability to produce good quantities of black (eumelanin) and red (pheomelanin) pigments and is the original gene of ancient wild cattle who had striking wild-type patterns. ED = a mutation that causes a suppression of pheomelanin, so the animal has primarily eumelanin (black) pigment with no ability to produce bold patterns. e = mutation that causes the suppression of eumelanin in most all of the animal except the eyes, and sometimes the nose, muzzle,tail, and limited other areas. So the animal is always mostly red (but can have some very limited dark (eumelanin) pigment on nose, muzzle, tail, and ears) e/e animals are mostly red but can have very limited touches of black pigment in very limited parts of the body. E+/e and E+/E+ animals can be anything from near black to near fully red including some dramatic patterns. The patterns are controlled by genes in other locations, including the agouti (pattern) genes. ED animals are usually entirely black (Eumelanin) but can have some limited red pigments (Pheomelanin). If the ED animal has two broken TYRP1 genes (b/b), then the black pigment will remain unfinished and will appear dun (brown). Now, since any animal (including e/e) can have at least some black pigment (eumelanin), then if the animal also has two defective TYRP1 genes (b/b), then whatever eumelanin is present, will be incompletely produced, and will be dun/brown So an e/e, b/b red animal can show some limited dun (instead of black) in those limited areas areas that have eumelanin pigment (like the nose, muzzle, tail, eyes). E+/e or E+/E+ animals that have the pattern genes to have quite a bit of black pigment (eumelanin), that also have b/b dun genes, will be a red with dun highlights (instead of red with black highlights). So imagine an E+ bull (similar to Conahir Outlaw who is a mix of red and black), but imagine him with b/b at the Brown Locus. This imagined bull would have his black (eumelanin) parts appearing brown (dun) because of the incomplete formation of the eumelanin because of the two "broken" TYRP1 genes and the inability to catalyze the eumelanin. Here's a picture of Conahir Outlaw, try to imagine what he would look like if his black parts looked dun. Attachments:
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Post by cddexter on Oct 27, 2012 14:43:46 GMT -5
ah, but since Outlaw doesn't carry any 'b' his mealy nose would be from a different pattern locus?
I think John mentioned he had a ED/ED that showed a definite brindling pattern in the summer, but more of a black on black, which was supposed to be impossible.
Thanks for posting, Kirk. LOVELY to have you with us again. cheers, c.
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Post by Cascade Meadows Farm - Kirk on Oct 27, 2012 17:49:38 GMT -5
ah, but since Outlaw doesn't carry any 'b' his mealy nose would be from a different pattern locus? I think John mentioned he had a ED/ED that showed a definite brindling pattern in the summer, but more of a black on black, which was supposed to be impossible. The mealy mouth/nose may simply be a standard effect of having two E+ genes.... Or there may be a pattern gene at some other locus like the Agouti locus that interacts with the E+ gene to cause the VERY common mealy mouth look. The mealy color is made from blending diluted black and diluted red pigments and has nothing to do with Dun. Concerning brindle and ED/ED, the ED gene does NOT eliminate pheomelanin, but simply overwhelms the pheomelanin with lots of black eumelanin. The brindling pattern may work by simply strengthening the black in some areas and weakening it in other areas. So theoretically, you might be able to see a hint of brindle pattern on a fully black animal, with two different shades of black.
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jamshundred
member
Help build the Legacy Dexter Cattle "Forever" Genotype database
Posts: 289
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Post by jamshundred on Oct 27, 2012 18:32:58 GMT -5
Kirk,
What a joy to see you back on the discussion groups! I personally have missed you lots!
I just took a photo last week of another red brindle bull. If I remember correctly he has a light blondish band at the muzzle. He is line bred on the sire side from the Lucifer bloodlines of LBI. His sire is a beautiful bull - looks quite similar to his ancestor Sylvan Ebony. He will be for sale - as soon as all the genotyping is complete. I need to take the photos off my camera and will try to remember to show a photo when I get that done. His dam is a Dun cow also with Lucifer in the pedigree.
Gosh it is good to see you back!
Judy
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