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Broomcroft
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Post by Broomcroft »

Is the choice of colours that make up the breed standard for genetic reasons, or is it just what people want?
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Kirk- Cascade Herd US
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Post by Kirk- Cascade Herd US »

Broomcroft wrote:Is the choice of colours that make up the breed standard for genetic reasons, or is it just what people want?
Coloration in breeds of livestock is usually by choice and is decided in the early development of the breed. Most breeds in their early stages lock in on a color choice (or some other identifying feature) in order to serve as an identification for that breed. Sometimes the original color is simply a color that the original breeders favored. Imagine if both Herefords and Angus were all pure black with no markings. It would be hard to develop separate identities and separate "brands" of beef. In Dexters, more variety of color is allowable because Dexters have somewhat easy brand/breed recognition beyond color - based on their size, dual purpose, and personalities. As an example to further support my theory, look at longhorn cattle - they have an amazing variety of color because their breed recognition is based on their unique horns.

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Duncan MacIntyre
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Post by Duncan MacIntyre »

The importance of colour as Kirk says is initially for breed recognition. In todays commercial market colour is very important in providing farmers with the abilty to present in a market a number of uniform calves. The uniform batch is much easier to market in many ways, and the colour of course is just one aspect. But if you put 10 steers in the sale ring which vary in weight by 20kg it is a lot more difficult to spot that if they are all exactly the same colour. So to a great extent it is to a breed's advantage if the calves are all of the same colour. The Dexter allows more variation than most, and maybe has needed less uniformity of colour due the different marketing methods than more commercial stock. However the present trend is to many more herds of substantial size in the UK and maybe we need to remember the importance of marketing store cattle more than we did in the past. Aesthetically I think brindle Dexters are great, but I suspect we already have enough colour variation without adding to it. My feelings on this are somewhat moderated by the fact that the brindle animals may just be an expression of the wild red, which we have in the breed through grading up and probably should accept, just as I think we should accept the polled genes. How is that for talking yourself into a corner?

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Post by Minnie »

Also, some scientists are stating that red or black have advantages in certain climates due to heat adaptability, some saying that red has advantages over black in much of the warmer areas.


Here in Northern NSW Australia, I've had quite a few people tell me in our area, that red cattle aren't as prone to Buffalo Fly as black cattle and it seems they're right.

Then on the other hand I've been told the pink nose and light colour around the eyes can have problem with skin cancer and pink eye as with herefords.

Regards

Vicki
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Broomcroft
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Post by Broomcroft »

We do as many pure reds as possible, because we like them, but pink noses worry me. Pink noses in horses are a problem with the sun. I had a horse that we used to have to put suntan lotion on every day. I've always assumed that this may also be a problem with cattle too, especially with our summers now here in the UK. I'm happier seeing a cow that has a red coat but a darker nose.

BUT.....having said that, when we talk about pink noses, what do we actually mean? I have had a very experienced judge look at my reds with what I would say are grey noses, and he said they were pink!
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Post by Louisa Gidney »

Are these wild type red or brindle animals associated with any particular lineages of Dexter? I'd never seen them until the progeny of one particular bull, that I acquired for his dairy background, arrived. One beautiful red bull calf turned black at about 6 months old. Out of interest, he was used on a couple of cows before going in the freezer. His son was also red at birth but at a year old is now a dark brindle, like the photo above, & is also destined for the freezer.
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Post by wagra dexters »

The train of discussion suggests that all black nosed reds are brindle, and go black. How can that be? I had a letter from an Australian lady, after she had visited Dovea, and seen Outlaw. It was a good few years ago, but he was a mature bull, and she describes him as having a coat like an Irish Setter dog, but with a darker head.

The only balck nosed red we have had that eventually went black, was a fifth cross steer from a jersey base line, and he had a slight brindle through him at birth.

Are they long pedigreed, the brindle-turned-blacks to whom you are referring, or are they upgrades? Margaret.
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Broomcroft
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Post by Broomcroft »

The owner of Emile, the little red/black-nosed that turned black, has contacted me to tell me she is still black but with a red stripe down her spine.
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Post by Penny »

Does she have a cream "jersey type" muzzle? I have had one like this, and seen another. Destined for the beef chain.
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Post by Broomcroft »

No, Emile has a black nose, but I do have a brindle out of the same cow, but different bull, that has a very clear creamy Jersey-type muzzle.
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Post by Kirk- Cascade Herd US »

wagra dexters wrote:The train of discussion suggests that all black nosed reds are brindle, and go black.

Remember, there are two kinds of reds, true red (little e) that only have red pigment, and wild-type red (E+) that have red pigment and also may be shaded by black pigment, depending on other shading genes.

A wild-type red can look exactly like a true red with no shading (I've got one or two), or it can have an array of black shading depending on the particular shading genes the animal might have. Most of these shading genes have likely been in the Dexter herd since the beginning of today's Dexter breed, but have remained hidden much of the time because the shading genes don't exhibit in black animals (or true-red animals).

Most of these shading genes allowed the old wild cattle predecessors, to adjust to particular environments to act as camouflage on the edge of wooded areas or in very tall grass. If we could DNA test for these shading genes (we can't yet) and tested the most purebred herd of old-time black Dexters you would find many of these shading genes in hiding.

This thread so far has mentioned some of the shading variations:

1. Black nose on otherwise red animal with little other shading
2. Pink/Grey nose on wild-type red
3. Jersey type markings
4. Dark full-body shading males only
5. Dark full-body shading males and females
6. Very Dark head, tail, and feet but red body
7. Dorsal (back) stripe
8. Brindle (striped somewhat like a tiger).

These shading genes are at mostly unverified gene loci. So it is not well understood exactly how many of them work and how you can mix and match them.

Both the E+ wild-type red gene, and these various shading genes have almost certainly been in the Dexter herd all along, hiding here and there, and only exhibiting very occasionally, usually to be quickly culled. But, as red has become more popular, it has allowed the shading genes to exhibit more frequently. Especially when some famous bulls/lines that happen to have a wild-type red gene (E+) are used, then very quickly, a lot of these shadings appear in many calves. The bull gets blamed, but in many cases, the shading is coming from the black or even true-red dams.

Because these shading genes likely are spread like peanut butter all throughout Dexterdom (including in blacks and true reds) culling them when they appear on wild-type reds isn't really doing much to eliminate these shade genes themselves. If you don't like the shading and want to hide it (since you can't really cull it out very well), you can breed for all black (ED/ED), true-red (Ee/Ee), or heterozygous black/true red ED/Ee. If your entire herd is these three combinations, you will never see the shading.

As far as the true-reds having cancer problems with light noses/light eyelids, it isn't the same as in Herefords. The pink or pink/grey (a darker muddy pink), in red Dexter's noses is well pigmented with phaeomelanin (red) pigment. It does a pretty good job of blocking the sun, but certainly not as good as the black pigment. In the case of white spotted animals, white spotting is the lack of all pigment, so the pink nose in those animals is just the blood showing through the mostly clear skin. This clear skin with no pigment, has no protection from the sun. Since (red) Dexters, don't have facial white spotting (lack of pigment), they don't suffer from this, like Herefords do.

Hope this helps,

Kirk
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Post by Broomcroft »

Kirk

I'm not going to ask you whether the wild-red gene is desirable or not because presumably that depends upon individual taste. But, genetically speaking, without any personal views coming in to it, are you saying that Dexters are so infiltrated with wild-red, and that it has always been there, that by removing it we are actually going away from "real" Dexters. I didn't put that very well but I think you will understand what I'm trying to say.
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Post by Kirk- Cascade Herd US »

Broomcroft wrote:Kirk

I'm not going to ask you whether the wild-red gene is desirable or not because presumably that depends upon individual taste. But, genetically speaking, without any personal views coming in to it, are you saying that Dexters are so infiltrated with wild-red, and that it has always been there, that by removing it we are actually going away from "real" Dexters. I didn't put that very well but I think you will understand what I'm trying to say.

Most older breeds started out as mixtures of whatever was around in the early going and occasionally had introductions of whatever nice looking animals drovers might have brought through the area. Then after generations of selection, a "breed" is born. With only 3 choices at the E locus (wild type, black, true red), and with the two red choices hiding behind black, and with E+ wild type red able to look like true red in some cases, the chances that Dexters or any other primarily black breed didn't have both of the two red gene types sprinkled throughout the breed would be astronomical (actually, astronomical squared).

In cattle breeds where color is an important identifier, the E locus genes that are out of character for the breed have been constantly culled. Since black is dominant, without DNA testing, the two reds can hide forever in a black breed and it's impossible to completely eliminate all red genes. Since E+ can look like true red (e) and because E+ is recessive to black, E+ can hide in both black and true red herds forever (without DNA testing to locate them).

The "real" Dexters have always had a minority of reds (some true red and some wild type), but perhaps all along, many of the wildtypes that also had shading genes (brindle, etc.) were culled out. So perhaps it has been traditional to attempt to remove these shaded animals and that act would reduce the frequency of the E+ gene. Perhaps if this discrimination is traditional, it would go against the "real" Dexters to stop this discrimination? Either way, it really does boil down to preferences of individuals and preferences of breed associations and does NOT necessarily reflect purity or indicate recent introgression.

Anyone disagree?

Kirk
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Post by Duncan MacIntyre »

I agree with all Kirk is saying, it is really good to have someone one the board putting the genetic technicalities so well.

We now have much more knowledge of the genetics of colour and of course of a lot of other things in cattle. The problem to me is how we apply these today to maintain a breed standard and to keep keeping Dexters a practical small holding or self sufficiency prospect, and also allow for the fact that there are larger herds emerging with commercial beef production albeit on a small scale compared to supplying supermarkets with mainstream beef.

We have to maintain a visually identifieable breed, and this is where accepted colour comes in and always has done. We have to decide if we are happy to keep Dexters as whole black, red or dun. I think that we should do this, as to widen the colour spectrum would result in such a multiplicity of colours that the breed would lose its identifiable character. It is for the same reason that I think we need to keep a very careful watch on the size of Dexters and not let them drift in to being larger than they have been in the past.

So to maintain our colour standards I think we have to accept that the brindles, red stripes, white stars on faces etc whilst they may as individuals be ok as part of a breed they fall outside the standard and should not be used for pedigree breeding and certainly should not be shown. The variation in colour should be viewed in the same way as a serious deviation in size or conformation would be. I do realise that we will never eliminate the genes causing these aberrant colours but we have to rule out the expression of these genes in the phenotype.

I have been having a big arument with myself over this in the last few days, having in the past rejected animals with brindling or red back stripes, but having thought it through and read Kirks posts I think the decisions were right.

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Post by Broomcroft »

Interesting. I read it the the way around and probably incorrectly! What I deduced from Kirk's explanation is that the brindle that is culled so that it doesn't get into the pedigree lines, is no more likely to produce another brindle than the black cow stood next to her.

The message I got is that unless you genetically test everthing and cull by the results not what you see, you'll always have brindles etc because it's in the black herd.

I'm getting out of my depth!
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