Animated Horse asset can be imported and used with Unity 4 Mechanim.

The model combined from 6 objects and has 2,129 polygons, 2,508 verts.
The horse has 52 bones which include 34 body bones and 18 additional bones for the armour and horseman.

The package also contains 3 different colour textures for the horse body, opacity, normals and specular maps.