A color example

[ctownson]

We have a cow here being bred to our herd sire Midas.

Midas is red, and carries dun.
The cow is black, carries red and carries dun.

A good example to calculate probabilities of the calf's color.

[ctownson]

Gene - you are definitely on the right track. I thought it was an interesting example. Midas is E+/E+ and B/b. So, he is heterozygous dun.

[cddexter]

well, let's see...

bull is red, carries dun. Since homo red overrides hetero and homo dun, both, and in the first post you didn't qualify which Midas is, nor which type of red he is, if you hadn't clairified it, the options from him would have been genetically:

e/e B/B
e/e B/b
e/E+ B/B
e/E+ B/b
E+/E+ B/B
E+E+ B/b

All the above options would give you a red bull carrying dun. However, you go on to say Midas is homo wild red and hetero dun. This limits the options to

E+/E+ Bb

cow is black, carries both red and dun. Cow can only have one red gene (because she's black and black is dominant and therefore present), and only one dun gene (because homo dun with hetero or homo black would produce a dun animal). Without knowing which 'red' she is, the options for her would be genically:

ED/e B/b
ED/E+ B/b

offspring could be any of the following combinations

E+/e BB giving a red animal not carrying any dun
E+/e Bb giving a red animal hetero for dun
E+/e bb giving a red animal homo for dun
E+/ED BB giving a black animal carrying red but not dun
E+/ED Bb giving a black animal carrying red and hetero for dun
E+/ED bb giving a dun animal carrying red
E+/E+ BB giving a red animal not carrying any dun
E+/E+ Bb giving a red animal hetero for dun
E+/E+ bb giving a red animal homo for dun

Did you want the percentages? ;D c.

[ctownson]

It is an interesting example since we don't know which type red the cow carries. In terms of having a dun animal from this breeding, the percentage is pretty low. Since we have not color tested every one of our animals, it is always a pleasant surprise when a dun calf is born from a mating like this one!

[cddexter]

morning, Charles. No wonder some people get confused about color. ;D c.

[ctownson]

You are absolutely right. Some of the most fun calls we get is when a calf is born and the owner does not know if it is red or dun and how did that happen when the cow they bought was black. Since we don't color test every animal, you get some unexpected surprises. I will often look back through a cow's pedigree and think the odds are very, very low that they carry red or dun. Then, sure enough, a red or dun calf is born when you least expect it. The various shades of the red and dun are also extremely interesting to me, but that is way beyond my genetic expertise I think.

[cddexter]

Charles, since this color thing is my thing (how fleeting fame : I thought I'd play a bit. I get phenotypic results of:
3 red, 1 dun and 2 black. That makes my results match Gene's However, if you include the recessive genes, or the genotypic results, then you have
1:8 chance of homo red with no dun
1:8 chance of black carrying red only
1:8 chance of black carrying both red and dun
1:8 chance of homo dun carrying red
1:4 chance of homo red carrying dun
1:4 chance of homo red and homo dun

It's amazing how one can go for generations and suddenly have color pop up when you least expect it. That happened with Sandi (Thomas) in 1988, and possibly with Charles Pacheco (Wee Gaelic) in 1993, and I remember seeing a one-off red cow down in Florida 15 years ago at the Kramer's (Beerex). Lucifer (ee) and Outlaw (E+E+) have a lot to answer for. cheers, c.

[ctownson]

Carol, that is what I got also. The confusing part to me comes in that you get a dun (phenotype) only one out of 8 times. So, when it shows 3 red, 2 black, and 1 dun that is not representative of how often it really occurs in terms of the phenotype for dun.

[cddexter]

yep.

What's even more fun is that you have a 25% chance of having homo dun, but because of the red override, you don't see it. I just love genetics.

There could be a good market for the offspring if someone wanted to breed to a dun, for dun. Lots of chances for more duns.

There's a special interest group in England that are now trying to 'prove' that Beryl brought dun in through animals that were misregistered crosses from something else, preferably Lincoln Red or Red Poll. They've done all this pedigree 'research' and have convinced themselves they've found skullduggery, not with Beryl, but with one of her foundation herd animals from another breeder. You could have heard a pin drop (oh, I guess with computers, it's a byte) when I pointed out that there's a ton of dun in the US from original foundation stock that predates any of the animals they are trying to claim are the culprits. I may have slowed them down, but I doubt that will stop the destruction, tho'. cheers, c.