#silver horse

[sadlittledrawings]

Dany rides her Silver

[horsesarecreatures]

Rocky Mountain Horse Mare Elixir’s Glamour Girl

[gallopavo]

(VERY BASIC) OVERVIEW OF HORSE COAT COLOR GENETICS Chapter 5: Silver

* Make sure to zoom in! The text is quite small, so it could be difficult to read!

The silver (Z) dilution is located in the PMEL17 gene. It is considered incomplete dominant due to the fact that homozygous (Z/Z) silvers tend to be more extremely diluted than heterozygous (Z/z) silvers, and are at a higher risk of MCOA (Multiple Congenital Ocular Anomalies). Silver is commonly called ‘silver dapple’ (especially in regards to silver black coats), and is referred to as ‘taffy’ in Australia. 

The silver dilution is responsible for silver bay and silver black coats. The dilution only affects eumelanin (black pigment) and, as a result, has no phenotypic effect whatsoever on red-based horses. Red-based horses can carry the silver dilute, as well as suffer from MCOA, but none of their coats will be visually affected. Silver dilutes shorter black hair to a ‘chocolate’ color in varying shades, while it dilutes longer black hair (mane, tail, feathering if present) to a ‘silver’ or ‘blonde’ color. 

Sometimes, silver bay (and even silver black) horses are mistaken for flaxen chestnut or flaxen liver chestnut due to their visual similarities, but they can be told apart by a few indicators. For example, silver causes intensely dappled skin which shows through the fur on black-based coats, striped hooves (visible on the soles), and light eyelashes. Additionally, bay horses already have countershading and visible black points (even when diluted or low-point) that red horses lack. Silver can occur on any bay phenotype (standard, seal, low-point).

As silver dilute horses age, their manes and tails may darken significantly at the roots, to the point where it can be difficult to tell they are positive for the silver dilute. Some non-silver bay horses, especially low-point bays, appear to have silvery or diluted eumelanin in their manes and/or tails (which is especially apparent when they are young), yet do not test positive for silver, and may not even be of a breed that carries the silver dilution. 

The silver dilution was first genetically localized and identified in 2006 (as being within PMEL17), though its phenotypic effects had been seen long before then. It is a very old mutation that is spread out across many breeds, including the Icelandic horse, which has not had direct contact with other breeds on the mainland for over 1,000 years. 

Other breeds known to carry the silver dilution include: American quarter and paint horses, Morgan horses, Rocky Mountain horses, Romani cobs, Tennessee walking horses, American Shetland ponies, American miniature horses, the Comtois, and the Ardennais to name a few. It is somewhat uncommon overall, but not very rare. 

The silver dilution has an interesting interaction with other dilutes when paired together. For example, when paired with cream (heterozygous), it dilutes eumelanin far more than heterozygous cream or even silver on their own would, producing a ‘caramel’ color in the points of silver buckskins and the coats of silver smoky blacks. 

When paired with the champagne dilution, some silver amber and classic champagnes cannot be visually distinguished from non-silver champagnes, as their manes and tails may remain dark throughout their lives. 

* MCOA (Multiple Congenital Ocular Anomalies) is a genetic condition caused by the silver dilute (Z) that causes ocular cysts, iris and retina deformities, enlarged corneas, and other eye issues. Horses that are homozygous for silver (Z/Z) show more severe symptoms, and may even suffer from blindness as a result. All silver horses, including red-based horses carrying one or two copies of the ‘Z’ allele, are at risk of this condition. 

Gene(s) involved: PMEL17 (Z, z)

Simplifying the possible genotypes that the silver phenotype could be tested for (along with each base):

E/- A/- Z/- (Silver bay) < "Silver brown" if on a seal bay base

E/- a/a Z/- (Silver black)

BONUS cream+silver dilutions

E/- A/- CR/n Z/- (Silver buckskin)

E/- a/a CR/n Z/- (Silver smoky black)

E/- A/- CR/CR Z/- (Silver perlino)

E/- a/a CR/CR Z/- (Silver smoky cream)

Sources on the silver dilution and MCOA: ↳https://en.wikipedia.org/wiki/Silver_dapple_gene ↳https://vgl.ucdavis.edu/test/silver ↳https://equinetapestry.wordpress.com/2012/02/20/silver-dilution-and-eye-defects/ ↳https://vgl.ucdavis.edu/test/mcoa ↳https://equinetapestry.wordpress.com/2012/11/12/aging-silvers/↳https://www.equinetapestry.blog/bay-silver-comparisons/↳https://www.equinetapestry.blog/buckskin-silver/↳https://www.morgancolors.com/silverdapple.htm 

[sweet-harmony]

… last Sunday of Advent before Christmas, this is my centerpiece for the week before December 25th... I think it was given to me as a gift 20 years ago. It's very precious—especially for sentimental reasons—and it couldn't have been more fitting for me, with a silver horse and white candles. A setter is missing, but we can work on it for next year with a good craftsman... who knows...

@sweet-harmony

[whywishesarehorses]

BLM Mustang for Sale - South Steens Boy

Named Silvio in the wild, this dude has stolen my heart.

So if anyone needs anything, I'll be figuring out which organ I can trade for his board

10 YEAR OLD CHESTNUT GELDING HORSE (7782) 15.1hh

(documented in the wild as being only 6)

[track2hack]

something something “insert quote about how majestic and beautiful horses are” something something

[vicpphotography]

- Ashanti -

Buy this photo and support Tara, a horse shelter in Poland ♡

[ahorseofeverycolor]

A celebration for the Southwind! She has gone on to a new home! The first of the big Barbie’s Dallas Horse to go to a new home via sale. Dallas herself is always vintage, probably 70s or early 80s, always middle-brown-tan, and with a waxy and unusual type of hair. You can still find this one 2ndhand but in poorly condition so I always grab her to customize. The sculpt is so pretty and realistic, not like the goofy/bogus looking ones of today. Horses used to be able to be beautiful and fun to play with, I wish that day could come again. She’s appeared here on Tumblr before, as the first all chrome horse I completed at this size, but it was time to take a bow now that she has sold to a happy home of a fantasy collector.