Liver is a term used to describe certain types of dark brown color

Color

Color or colour is the visual perceptual property corresponding in humans to the categories called red, green, blue and others. Color derives from the spectrum of light interacting in the eye with the spectral sensitivities of the light receptors...

 in dog

Dog

The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...

s and horses.

In dogs, it is a dark

Dark

Dark commonly refers to darkness, the absence of light.Dark may also refer to:*Evil, sinister or malign*Dark , a term used to describe a broadcasting service that has ceased transmission...

 brown

Brown

Brown is a color term, denoting a range of composite colors produced by a mixture of orange, red, rose, or yellow with black or gray. The term is from Old English brún, in origin for any dusky or dark shade of color....

 shade.

In horses, "liver chestnut" is a term used to describe a chocolate-colored chestnut

Chestnut (coat)

Chestnut is a hair coat color of horses consisting of a reddish-to-brown coat with a mane and tail the same or lighter in color than the coat. Genetically and visually, chestnut is characterized by the absolute absence of true black hairs...

 horse. A liver chestnut is the same genetically

Equine coat color genetics

Equine coat color genetics determine a horse's coat color. There are many different coat colors possible, but all colors are produced by the action of only a few different genes. The simplest genetic default color of all domesticated horses can be described as either "red" or "non-red", depending...

 as a regular chestnut, but the shade is a dark brown rather than the reddish or rust color more typical of chestnut. A horse that appears to be a liver chestnut but has a light colored mane

Mane (horse)

The mane is the hair that grows from the top of the neck of a horse or other equine, reaching from the poll to the withers, and includes the forelock or foretop. It is thicker and coarser than the rest of the horse's coat, and naturally grows to roughly cover the neck...

 and tail, sometimes colloquially called a "chocolate palomino

Palomino

Palomino is a coat color in horses, consisting of a gold coat and white mane and tail. Genetically, the palomino color is created by a single allele of a dilution gene called the cream gene working on a "red" base coat...

," could be a horse manifesting the champagne gene

Champagne gene

The champagne gene is a simple dominant allele responsible for a number of rare horse coat colors. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively...

. However, "flaxen" or light-colored manes and tails are also seen in chestnuts.