Genetics and shikoku black an tan

Hello all, I would love to speak with you about my experience with genetics and shikoku black an tan.

I'm not a genetic specialist so if anyone of you are more inside with this tematic (for sure a lot my collegue breeders) please correct me if i write a mess.

As far as Black an Tan shikoku are not SO RARE.

All depends on which combination you are doing in your mating.

the basics are:

- ay is red gene

- at is black gene

- aw is called agouti gene

- phenotype is the char that appeare in your dog (in this case the color you are looking on your dog)

So we can have:

1) ay ay (red) -phenotype-> only red

2) ay at (red black carried) -phenotype-> red sesame, some dogs CAN appeare sesame, they have some dark in the face, but the black is stopped before arrive btw the ears, and if mated with other dog ayat you can have black and tan puppies

3) ay aw (red sesame carried) -phenotype-> red sesame the dark on the face in usually is more homogeneous

4) aw aw (sesame) -phenotype-> only sesame 

5) aw at (sesame black carried) -phenotype-> dark sesame the dod is very darker in usually

6) at at (black an tan) -phenotype-> only black and tan

please take a look on this article for see pics

That's neam Mendelian genetics application, so we can calculate the colors probability in a litter using punnett square, that's an example:

In those example only the 25% of the puppies in a litter with ayat dogs can be black and tan with both the parents black gene carrier.

For Increase the probability we have to use two black and tan dogs or one black and tan dog and one black carrier:

so in this combination we can have 50% of the puppies black and tan.

Find out two parents both black and tan in shikoku is really hard, because the common genetic used in the combinations is awaw.

In my kennel i had two lines both black and tan carried, so I got some black and tan puppies.

But some of them were born prematurely, others during the first two weeks after the birth were a bit less strong in health and so bring them out from this prenatal apathy were very hard.

For luckly some of them are now adult beautiful shikokus and are living nicely with their family.

That's for tell that is possibile to have black&tan puppies in 2 generations, but since there is quite hight risk to loose then so early, I'm very afraid, and I would not plan my selection for having this color.