Tobiano Suppression - A Study

[Silverine]

Purchased two new AC mares to add to my experiments, a Prze and an Arabian.

First foal from the Arabian crossed with my full white stud:



I'm not surprised at the lack of white. This filly will eventually be crossed with my Prze x full white GV colts.

The parents:

[Silverine]

Further evidence for suppression. A filly from dual Prze x full-white parents.




Parents:




Based on my experience with her full-white ancestors, I would consider this filly to have almost exactly 50% of their white expression. That near hind leg is well known in my lines for remaining stubbornly colored.

I find it interesting that this filly is split in half as she is, rather than having patchier white coverage of her whole body. But her lines are known for smooth demarcation of white and colored areas, so I suppose it's not particularly surprising. It will be very interesting to see what this cross throws the next time it gives me a marked foal.

[Silverine]

Funny story, turns out that foal with the one high stocking actually has face white as well. Apparently my lines also like to throw the game's tiniest stars:





Good thing I checked on her before her hair grew in.

[Silverine]

Another filly from two Prze x full-white parents:



Interestingly this one also sports a facial marking but no legs.

I've started wondering if different unmarked AC breeds would give different coverage when bred with the full whites. For example, would two Caspian x full-white offspring offer front coverage rather than back? I do have the Arab x white filly aging up so it will be interesting to see what she gives when crossed with the Prze x white boys.

[Silverine]

An interesting colt by a Prze x FW stud and out of a socked Forest Horse x NAB mare.




Parents:





This foal on its own would not necessarily have come to my attention if I weren't already looking into this. The dam has markings so the foal has an obvious source for tobiano. The more interesting aspect is the coverage of the foal.

If my three-allele model is correct, the sire should be A/C and the dam should be B/C (C from her body-marked sire, B as she only has socks and face white). The foal then is C/C or it would not show body white. But again, this is assuming that my model is correct.

What I find more curious is why this foal should have neck coverage, but not the offspring from two Prze x FW parents. Hmm.

[Silverine]

Latest foal from Prze x FW parents:



Interesting that this one got the neck white instead of the butt.

[Color Guide]

Here's a fun one. No tobiano in parents or grandparents. Popped up with a stocking.

[BlackOak2]

Here's a fun one. No tobiano in parents or grandparents. Popped up with a stocking.

I've had these type pop up too. Tarpans do it to me all the time. Thought it was mainly because of glitches from the AC (many of the horses were glitches), but I did learn that not all of them were glitched.

I don't know exactly what I have running around in my Lp tarpan line, but I'm thinking it's patterning without the switch. But not sure how to actually offer that with the way the 'slippage' is theorized.

...
Okay, I just don't want to think about the How, trying to beat a bit of a migraine these past few days.

[Color Guide]

I've had these type pop up too. Tarpans do it to me all the time. Thought it was mainly because of glitches from the AC (many of the horses were glitches), but I did learn that not all of them were glitched.

I don't know exactly what I have running around in my Lp tarpan line, but I'm thinking it's patterning without the switch. But not sure how to actually offer that with the way the 'slippage' is theorized.

...
Okay, I just don't want to think about the How, trying to beat a bit of a migraine these past few days.

If Tarpans are a mix of A and B suppression (A = no white, B = socks and stars/stripes), you could have a bunch of horses that are A/B and then throw a B/B who suddenly has a mark.

Alternatively, you could have some with To and no white genes, and other with white genes but no To, and then they pair up and you get To with white genes.

Or it could be both.

We won't know for sure unless/until Tom/Larissa reveal the mechanism or genetic testing is released.

[BlackOak2]

If Tarpans are a mix of A and B suppression (A = no white, B = socks and stars/stripes), you could have a bunch of horses that are A/B and then throw a B/B who suddenly has a mark.

Alternatively, you could have some with To and no white genes, and other with white genes but no To, and then they pair up and you get To with white genes.

Or it could be both.

We won't know for sure unless/until Tom/Larissa reveal the mechanism or genetic testing is released.

Yeah! That's what I meant!

I actually think that Tarpans have a good mix of both To and no To at all. As long as I pay attention to the ones coming out of the AC, it's decently easy to get rid of markings. For the most part, as long as you choose the unmarked Tarpans, it's less than 50/50 that any babes will pop with it.

Regardless, thank you for re-wrapping my head around that.