"Agouti hairs: Hairs marked with alternating bands of light and dark color and ending in a dark tip. In the tabby pattern, agouti hairs compose the lighter areas of the coat. "
I know it refers to cats but presumably it means the same with other animals as well. I have seen photos of brindle ponies, and a fascinating one of an Icelandic that was sort of liver and tan (I think) skewbald without the white.
Tabby ponies! Now, wouldn't that just put the cat amongst the pigeons colour trend wise!