colorgenotypediscussion9

POSSIBLE COLOR GENOTYPES

CHESTNUT & CHESTNUT-to-GREY

Introduction

The Basics

What Makes Grey (G)

What Makes Black (E)

What Makes Bay & Chestnut (A)

Possible Color Genotypes

Possible Color Genotypes/Black & Black-to-Grey

Possible Color Genotypes/Bay & Bay-to-Grey

Possible Color Genotypes/Chestnut & Chestnut-to-Grey

Sample Matings

Glossary of Terms Conclusion Return to HOME

Chestnut

ggAAee -- There is no dominant silvering allele (G) needed to produce grey, there are only dominate Agouti alleles (A) needed to produce bay, and no dominant extension alleles (E) needed to produce black. This horse will have only red hair, but if bred to a horse contributing a dominant E allele, its offspring will always be bay. This horse could also have grey offspring if the other parent contributes a dominant G allele. Without an E allele or a G allele from the other parent, its foals will all be chestnut. It will ALWAYS pass on the dominant A allele to its offspring for a potential bay in a future generation.

The Storrm Prinncess is an example of ggAAee.

She can only have chestnut or bay progeny.

ggAaee -- There is no dominant silvering allele (G) needed to produce grey, there is one dominant Agouti allele (A) needed to produce bay, and no dominant extension alleles (E) needed to produce black. This horse will have only red hair, but if bred to a horse contributing a dominant E allele, the offspring will be either bay (if this horse contributes a dominant A allele) or black (if this horse contributes a recessive a allele). This horse could also have grey offspring if the other parent contributes a dominant G allele. Without an E allele or a G allele from the other parent, its foals will all be chestnut.

ggaaee -- There is no dominant silvering allele (G) needed to produce grey, there is no dominant Agouti allele (A) needed to produce bay, and no dominant extension allele (E) needed to produce black. This horse is considered to be homozgous recessive chestnut. It will have only chestnut offspring unless the other parent contributes a dominant E allele to produce black, OR if the other parent contributes both a dominant E allele and and a dominant A allele that together would produce a bay. This horse could also have grey offspring if the other parent contributes a dominant G allele.

A chestnut foal will be reddish in color with its lower legs being much lighter, almost creamy-colored. Its mane and tail could be lighter in color than the body (flaxen), the same color as the body hair, or darker (but not black). It is often very difficult to discern white markings on its legs since the other hair is so light-colored. To find white markings for registration purposes, it is usually helpful to wet the hair on the legs to find any pink that will be under the white markings that will show later.

StorrmyZ Dezert Sunn-3 weeks old

StorrmyZ Dezert Sunn-9 months old

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Special Note: A light-colored or parti-colored hoof is an indication of white markings above the light-colored part of the hooves. Dark hooves usually do not have any white marking touching them. Of course, the hooves of a newborn foal might be very difficult to tell whether they are light, dark, or parti-colored. It can take awhile for them to be what they will be as an adult. Therefore, if at all possible, wet the hair to find pink skin and draw it on the registration application--even if you aren't sending it in immediately. (Once the foal gets bigger and more active, it might be harder to get them to stand still long enough for you to draw the markings later.) The hoof will be light colored where the pink skins "touches" the hoof.

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Chestnut-to-Grey

GgAAee, GgAaee, or Ggaaee --The base foal coat will be chestnut, but this horse will turn grey as it ages. This horse's offspring will have a 50/50 chance of being grey based upon this parent's contribution.

GGAAee, GGAaee, or GGaaee --The base foal coat will be chestnut, but the horse will turn grey as it ages. This offspring is considered to be homozygous grey since it has two dominant G alleles. This horse's offspring will always be grey because it will always contribute the dominant G allele.

This foal's coat coloring makes it even more difficult to find white markings. It is important to draw the markings of the head early on, before the silvering progresses very much, so that any white area can be drawn accurately and indicating the presence or not of pink skin under the white hair. Look for the head to turn grey before the rest of the body. As with the other colors turning to grey, the mane and tail might change to grey before the body, or it might retain more of the original color for a longer time.

Bint Ibn Sahanad--about 5 weeks old