Dun
Dun is a dilution gene that restricts pigment from the coat, leaving behind a dorsal stripe and dark points. This gene affects the coat in the same way, regardless if it's heterozygous or homozygous.
The geno code for dun is written as:
nDn or DnDn
Chestnut + Dun
'Red Dun'
Can range from a vibrant red to a rich liver brown. The skin will still be a dark grey or black, the eyes will be brown, and the mane, tail, points and dorsal stripe will be a darker shade of the base.
Black + Dun
'Grullo'
A desaturated coat ranging from an ash colour to a dark charcoal with dark points, mane, tail and dorsal stripe.
The skin will remain a dark grey or black and the eyes will be brown.
BAY + DUN
'Classic Dun'
The most common and recognized version of dun, this coat can range from a pale gold to a soft reddish tone, to a darker brown in color. Classic dun displays darker dun points, and a black mane and tail. Wild classic dun will visually be the same, with the dark leg points restricted to the ankles.
The skin will remain a dark grey or black and the eyes will be brown.
Mealy + Dun
'Olive Dun'
Darker and richer in color than classic dun. Exhibits black points, black mane and tail.
The skin will remain a dark grey or black and the eyes will be brown.
Special Characteristics of Dun
Dun creates what is known as 'primitive' marks. These marks are always the same color across the coat and darker than the base.
Dorsal Stripe
Always present, the dorsal stripe is a narrow band of colour that runs from the wither to the tail.
Dark Points
Always present, dun will create darker points along the knees, hocks, ankles and face.
Leg Barring
Frequently occurs, but not required. These are stripes/bars that are concentrated around the hocks and knees.
Shoulder Barring
Frequently occurs, but not required. These are stripes/bars that are concentrated around the withers.
Fish Boning
A rare form of barring, this factor creates barring across the rump.
Cobwebbing
Frequently occurs, but not required. Cobwebbing is the stripping of the forehead.
Frosting
Common, but not required. Dun will often creating frosting of the mane and tail. On the mane, the frosting will occur on the edges. On a roached or upright mane, this will create a 'sandwiched' look, with a dark center between two lighter layers.
DUN + SOOTY
When dominant dun combines with sooty, the markings may interact into what is called a Bider mark. The sooty will concentrate into a mottled, lacy marking extending from the wither down over the shoulder.
