See Horse Welfare Advocacy Resources for a list of documents pertaining to horse slaughter issues.

Herd communication and behavior
Observing a domestic group (Rick Gore)
Stallions fighting
Horses re-establishing relationships
Horses setting space boundaries (Marlis Amato)
Mare teaches new-born to follow (Marlis Amato)
Bullfight training (Merlin/Orpheo and Rafi Dumond)
Buck Brannaman riding in clinic
Horses pursuing worming meds (Marlis Amato)