Mackerel Tabby - A mackerel tabby has narrow stripes that run in parallel down its sides. This is what some people refer to as a "tiger cat." The body has narrow stripes running down the sides in a vertical pattern. Ideally the stripes are non-broken lines; evenly spaced. They branch out from one stripe that runs along the top of the cat's back down the spine, resembling fish skeleton -- which is why the term "mackerel" is used to describe it.
Despite his markings might lead you to believe, "Tiger" is actually a fully registered Morgan. He has Splashed white markings. This type of marking is very rare. It creates a very crisp line between the white markings and the horse's base color. It's almost like they were dipped in white paint. Tiger is also a buckskin.