Color question

[Star Creek Dexters]

I have a Dun heifer whose parents where: Sir Dun/Black, Dam Dun/Dun

I have a bull who's either Red/red or Red/Dun

Am I right to come to this conclusion: Bull bred hiefer, if heifers calf is black than bull is Red/red if heifers calf is dun than bull is red/dun?

[ctownson]

It is a bit more complicated than that. Dexter colors are carried on two genes, not one. I believe there is a good summary on the ADCA web site under the topic of color/genetics.

[cddexter]

Since there are FOUR genes and two loci involved from each parent, and you have mixed the loci together, the answer is more complicated. the Red is at one loci, the dun is on another, so red/red and red/dun don't compute as comparatives.

heifer if dun, must carry black, and be homo for dun. You don't say if it's likely to have a red gene, too.
bull if red, is homo red, no black, but may carry dun.

So, assuming heifer does NOT carry red, and bull is red but may carry dun, then you will have either a black calf, carrying both red and dun, or a dun calf carrying red.

If heifer does carry red, and bull is red, then you could have either a black calf carrying red and dun; a red one with one or two dun genes (red overrides dun); or a dun one, carrying red.

HEIFER CAN BE BB dd or Br dd: homo black, homo dun, OR hetero black and red, homo dun
BULL CAN BE rr bd or rr dd: homo red, homo dun, OR homo red carrying dun

Thus offspring can be Br dd OR rr dd OR Br bd OR rr bd: dun OR red OR black or red

You need to provide more info for a more definite answer. good question, tho'. c.

[Star Creek Dexters]

There is SO much to the color genes! I have read and re-read. It's just a learning curve that I am determined to conquer! =)

Here are the links to the bull and heifer's pedigrees. Hopefully that will help.
www.dextercattle.org/pedigreedb/ponyweb.cgi?horse=016967&HorseName=kooper&Page=1&Sort=0
www.dextercattle.org/pedigreedb/ponyweb.cgi?horse=023437&HorseName=madaline&Page=1&Sort=0

Thanks to anyone who takes the time to look at this, I really appreciate it!

We are pulling tail hairs on Kooper, our bull this week to test for color, since his dam was not color tested.

[ctownson]

Send in the tail hairs and then you will know for sure. We have only tested our bull (who is red) as it would be expensive to test all our cows. Our bull came back wild red, but also carries dun. Thus, he could produce all 3 dexter colors. Once you get the color test back, you will be able to make some accurate predictions for future breedings.

[legendrockranch]

That's what I suggested she do also Charles, have Kooper color typed.
On a side note I knew Midas stood a chance of carrying dun, but never tested his red dam. You just confirmed to me that she has to carry dun, since his sire did not. So he got the dun gene from his dam. Thanks

Barb

[Star Creek Dexters]

Ya, my head hurts again =) But I think I got the jest of it. I understand the concept, I just can't completely wrap my head around it yet!

[cddexter]

Kim, it's actually easy. Since in Dexters the E+ gene Gene refers to is always red, most of the time we simply refer to red without getting into deep arguments about which kind, especially since both the E+ wild gene and the usual recessive red act the same way.

If you remember that BLACK is dominant to both reds, you'll be half way there.

If you remember that dun is recessive so there have to be two to see the dun color, and it only gets expressed (you can see it) if the animal has a BLACK gene (one or both of the pair, doesn't matter), AND that both reds always cover up dun (homo red, homo dun is red to look at), it's a piece of cake.

The heifer could be BLACKBLACK or BLACKred at the base locus (has to have a BLACK gene for the dun to show), and MUST be dundun at the dun locus (recessive so both genes of the pair must be dun to show).

The bull MUST be redred at the base locus (red only shows if there are no BLACK genes), but could be either blackblack, blackdun or dundun at the dun locus (dun is always covered up by red).

So....to break it down, the combos from BLACKBLACK (heifer) and redred (bull) would all be BLACKred. The other combo of BLACKred (heifer) and redred (bull) would be BLACKred or redred. This gives you only two choices of base coat color combos from those two animals: BLACKred or redred.

Then look at the dun locus: the heifer MUST be dundun (because she's dun and it takes two recessive genes to show), and the bull could be either blackblack or blackdun or dundun at that locus because those are all the choices available and without a color test you can't tell unless he's thrown other calves that were dun, too, and since red covers up dun, you have no way of knowing what he's inherited over time from the various ancestors.

So.....at the dun locus, you could have dundun x blackblack OR dundun x blackdun OR dundun x dundun, giving you the following optiions: first would all be blackdun; the second would be blackdun or dundun; the third would all be dundun, making really only two choices again: blackdun or dundun.

Now......... combine those two sets, and you're there:
Option 1:
Base locus: BLACKred
dun locus: blackdun or dundun

BLACKred x blackdun = Black animal (only one red gene, only one dun; both are recessive and need two to be expressed)

BLACKred and dundun = dun animal (two recessive dun genes on a black animal. Red doesn't show because it's only one gene and recessive)

Option 2:
Base locus: redred
dun locus: blackdun or dundun

redred x blackdun = red (no BLACK gene at the base locus and red overrides dun)
redred x dundun = red (no BLACK gene at the base locus and red overrides dun)

The only thing to watch for is the label of the not-dun gene at the dun locus. It's called black but it's different from the base locus color of BLACK, and I believe doesn't have any effect on visible color (have to check with John or Sheila on that).

off to bed as have to be up by 5 am my time to go to work. I`ll be home again around 3, or I might have a chance to check here while at work. Let me know if the above helps. regards, c.

[Star Creek Dexters]

It does help! Thank you Carol!
I still can't figure out what Kooper might be, so I will just color test him and have a much better platform for figuring all this out! =)

[ctownson]

The color test is easy to do. While you are pulling tail hairs you might want to consider if you want to do any more tests at the same time. That way you will only have to pull the hairs one time.

[Star Creek Dexters]

He's been Geneo'd, and tested for PHA and Chondro, and A2 milk, so I think this is the last thing left to test for, LOL!
So will I do a color profile on him? or just test for one or the other color? I think color profile.

In the case that he carries Dun, I should go back and test my other foundation cows to aptly predict what colors the combinations can throw, right? But if he does not carry dun, then I would not have a chance of throwing dun calves, only black or red, right?
If he doesn't carry dun, then I would not have to test other red calves to see if they were dun or red, correct? Because if the bull doesn't carry dun, and the appears red, he is red. Am I right in that assumption?

We are not breeding for a specific color, rather for conformation and milkiness, but I have never been a good one at waiting to see what it is going to be! Like to have everything planned out and know before hand! =)

Thanks again so much for all you help!

[ctownson]

Yes, the color profile is what you want.

[Star Creek Dexters]

OK, Thanks! I will let ya'll know as soon as I get the results!

[cddexter]

Carol D used to get paid for doing stuff like this. Nice job, huh

gene, ? c.

[Star Creek Dexters]

Got Kooper's color test back!
e/e B/b