Re: question on "sable" coloration

Amy Dahl <amy@xxxxxxxxxxxxxxxxx> wrote in
news:44D884BE.874BE4E8@xxxxxxxxxxxxxxxxx:

Chesapeake Bay retrievers,
They are all bb, and vary from dark brown to pale buff

I haven't seen with my own eyes anything but solid pale browns in this
breed, but I've seen nice photos of several A locus patterns. So your
colors come from 3 different traits, which are inherited separately:

1. pattern (mainly A locus)
you have at least:
- dominant black (solid brown, any shade)
- sable (mainly yellow/tan dog with some darker shading
- tanpoint
- saddle (or perhaps wolf pattern? haven't seen enough pics)
- brindle, which creates stripes over the pale parts of any pattern.

2. shade of eumelanin
varies from very dark brown to very faded "deadgrass".

3. shade of phaeomelanin
varies from dark tan to creamish, and is visible only on dogs which are
not solid brown. Darker shades make it hard to see the pattern, as brown
eumelanin and rich phaeomelanin can be very close to each others. Dark to
medium shades seem to be most common in this breed.

This site has a nice photo collection of patterns and shades:
http://www.geocities.com/Petsburgh/Farm/1276/colours.html

What I have been wondering for some time
is whether some of the "brown" dogs are in fact very dark
tan, either sable patterned or some other A locus pattern
where the brown is nearly indistinguishable from the tan.

Yup, very likely. Look at these pages:

http://www.geocities.com/Petsburgh/Farm/1276/deadgrass.html
the pup is clearly a dark-masked sable, and as its phaeomelanin is quite
pale, it is quite easy to see where it has brown hairs and where just that
yellow.

http://www.geocities.com/Petsburgh/Farm/1276/sedge.html
These "sedge" dogs are not solid brown, but some borders between darker and
paler can be seen especially on face. The pattern might be some kind of
sable, but as its eumelanin is non-dark reddish brown and phaeomelanin is
reddish tan, the real edges are very hard to see.

base, being darker brown from there to the tip. His ears
appear darker right around the edges. Does this sound like
sable pattern in a puppy to you?

Yes. Here is a pale cream Finnish Lapphund dam with both cream (ee) and
sable pups:
http://lapikas.net/varisivut/varikuvat/pennut/sp3.jpg

What other breeds are known to have very dark tan?

About all breeds which have been bred to be "brighter" and "prettier". All
setters, all spaniels, Dobermann and Rottweiler, many GSDs, several hounds,
St Bernhard etc. And any dogs which dark hair tips over tan base color look
darker than pure tan dogs.

Liisa

.

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