Colors and Patterns of the Icelandic Sheep

Every Icelandic Sheep is either a Black sheep or a Moorit (brown) sheep.  That is to
say that, genetically, they carry a “color” gene, from which they can express either
Black (dominant) or Moorit (recessive).  

Icelandic Sheep also have a “pattern” gene, from which they can express and carry
the following:
White (dominant over other patterns and solid)
Mouflon
Badgerface
Grey
Grey Mouflon (single gene)
Solid (the absence of a pattern)

The pattern gene tells the follicles NOT to produce color, so where the pattern is
expressed, is where the animal is NOT expressing their base color black or moorit.  
The pattern listed above called “solid” is the absence of any pattern that tells the
follicle not to produce color.  However, solid sheep can occasionally express genetic
and environmental effects such as “frosting,” phaeomelian pigmentation and a deep
rust color.  These are more like birthmarks and can be passed down in families without
consideration for the color or pattern of the sheep.

Sheep may express two patterns at once, having been given a pattern from each
parent, that express equal amounts of dominance.

Sheep who express the pattern called “white” may also express another pattern, but it
may be unknown to the shepherd, since “white” tells all of the follicles not to produce
color.  If another pattern is suspected, the sheep may express a dalmation-type skin,
and may produce offspring with the “hidden” pattern.

Spotting:
When people imagine spots, they often think of the colored portion of the sheep as
being the “spot,” when the opposite is true.  The “spot” is the portion of the sheep
where the follicle has been altered to NOT produce color.  The spotting gene is
recessive.  Both parents must carry spotting for the offspring to express spotting.  It is
not carried on the pattern gene, but works like the above-mentioned “birth mark” type
expressions.

Below are some of the expressions of patterns and color within my flock.
Icelandic Sheep
Moorit + Grey.  This lamb's color is moorit and pattern is grey.  Her
mother is also moorit grey, but her father is ablack badgerface, who
carries a moorit gene.  Grey lambs are often born appearing to be a
solid color, but soon develop silvering in their ears and the
well-known "sugar lips," which gives a tell tale sign that the lamb will
continue to lighten and become grey.  She is pictured to the left with
her mother, Fjola.  Fjola shows how light the moorit grey can be in
adulthood.
Black + Grey.  These two ewes both have the color Black
and the pattern Grey.  Silfa (below) has more prominant
sugar lips than Ipa (left).
Mouflon.  Finna (one of my favorite ewes) is a Moorit
Mouflon.  Her color is moorit and her pattern is mouflon.
 At left, she is shown with her 2007 lambs (both black
mouflons, detail below).  The mouflon pattern is shown
with silvering in the ears, check marks by the eyes, and
a "boston cream" color below the chin, stomach, and
rear of the sheep.
Badgerface.  Pictured here are two black badgerfaces. (their
color is black and their pattern is badgerface).  Badgerface is
shown by a creamy pink color (sometimes also has shades of
cream and a greyish color) on the body, and a mask-like
pattern on the face.  The inside of the ear has no silvering,
but the outside of the ear has silver tips.  Remember here that
the pattern is the part of the sheep that is NOT displaying the
color.
White.  These three photos show white sheep.  The
ewe to the left (Ising) has dalmation skin, and we
suspect she is a black sheep with a badgerface and
white pattern expressed.  She has had several
badgerface lambs from rams with various patterns.  
She also displays phaeomilian pigment on the crown
of her head.
Solid (the absence of a pattern).  All follicles display the
color of the sheep.  The two sheep pictured here are solid
with a black color gene.  The ewe below has some grey
frosting on her rear, which is mostly an environmental effect,
and is not to be confused with the grey pattern.
Badgerface expressed over Black.
Badgerface expressed over Black.
Badgerface pattern and Grey Pattern expressed over Moorit.
(above) Ewe is Moorit Mouflon, lambs are Black
Mouflons.  (right) Sven, a Black Mouflon.