GO2Altitude Equine Hypoxic Training Systems (hypoxicators)
Drug-Free Performance enhancement equipment
http://www.go2altitude.com/horse.html

Nature Vet Australia
http://www.naturevet.com.au/

Equine respiratory system
http://vetgate.ac.uk/browse/cabi/21744d0b938b85ce6b28c668264523e7.html