When you are fighting against cavalry, all blows are struck against the rider using the rider's Weapon Skill and never against the mount. A mount fights using its own Weapon Skill if it has its own Attack.
Source: Warhammer Fantasy: 6th Edition
When you are fighting against cavalry, all blows are struck against the rider using the rider's Weapon Skill and never against the mount. A mount fights using its own Weapon Skill if it has its own Attack.