03/10/2024
At first glance one might think that these two pigs are both chocolate selfs.
It is a fairly common occurrence that the color of the pig on the bottom of the first photo is confused for chocolate. It is a "shaded" color known as Sable or Sepia (depending on the shade, genotype, and also who you ask). It is not recognized by the ARBA standard. Sometimes Sepia/Sable is even unknowingly selected over chocolate because it has a tendency to be a few shades darker and less prone to grizzling, both of which are desirable chocolate qualities.
Typically when first born, sable/sepia often looks indistinguishable from chocolate. As they mature their face and skin will continue to darken, and their coat body color follows to various extents. This shift to a darker shade is why sable/sepia are referred to as "shaded". The darker face/top coat on older animals can sometimes be chalked up to faded chocolate (especially on long haired breeds). The easiest way to differentiate is skin color. For chocolate, ARBA standard calls for a "rich dark chocolate color with eyes and feet to match." Black ears or feet are a DQ.
Chocolate pigs will have chocolate feet/ears that match the coat color for the entirety of their lives. Sable/sepia develop black feet, ears, and black toenails. Their skin tone can appear lighter and passible as chocolates when babies, but around weaning age or later the difference is noticeable. The black ear/feet disqualification in the chocolate standard helps avoid this confusion, but it still happens from time to time, and not just in self colors. It is even easier to mistake them in marked varieties. By the ARBA standard's definition, pigs (in any variety) with black feet/ears/skin are not chocolate and should not be shown as chocolate or referred to as chocolate on pedigrees.
Sometimes as adults, sable/sepia end up dark enough that they can pass as a poor faded black color. The easiest way to identify a sable/sepia from a black is under color. Sable/sepia pigs will retain some of their original brown hue in their under color. Faded blacks, on the other hand, will maintain a more true black hue and fade to a lighter grey instead of a browner shade.
And as a side note, the genes responsible for sepia/sable are recessive. If you breed it in you will likely see more of it later on. If you want sepia/sable pigs that is fine, but if you are really wanting chocolate or black, not so much.
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This is updated from a cavy group post I wrote four years ago. It was suggested I post it on my page as well. This post is referring to phenotypes and how to identify sable or sepia. While I'm always down to talk about genotypes, I purposely stayed away from genetic "alphabet soup" as there are plenty of amazing resources to learn the associated genotypes. And I apologize for the fuzzy pictures, these are two wiggly junior pigs from the original post. 😅