Horse Allergies

Causes of Horse Allergies

Many different items commonly found in any horse’s environment can cause allergies. Stabled horses are engulfed in dust, mold spores and other allergens all day long. Even in fields where horses graze, there are many different proteins that could potentially cause an allergic reaction. Usually a horse can fight off these allergens with a healthy immune system, but not in every circumstance.

Signs of Respiratory Allergies

Recurrent Airway Obstruction (RAO) is the term used for respiratory allergies in horses but is also referred to as COPD or heaves. The symptoms can include coughing, exercise intolerance and nasal discharge.


* Dauvillier J, Woort F. T, Van Erck‐Westergren E. disease (2018) Fungi in respiratory samples of horses with inflammatory airway, Journal of veterinary internal medicine, 2018;1-8

What can be done?

Horse owners should take great care to remove the dust from the horse’s breathing zone, and this means treating the fodder so that respirable particles are kept to a minimum during feeding. 


Studies by Moore-Colyer and Fillery, (2012) and Taylor and Moore-Colyer (2013) have shown that steaming hay with a Haygain hay steamer, which drives steam throughout all of the hay and ensures temperatures of over 100°C are reached, is the only sure way to reduce respirable particles, mould and bacteria in hay.



What the Champions say

“I love using Haygain Steamed Hay because it helps improve my horses’ respiratory conditions and stopped them from coughing,” “With Haygain’s help, I can make sure the hay wherever I go is never dusty and it’s bacteriafree, so my horses don’t have any issues during competitions.”

Jessica Springsteen, Team USA
American Gold Cup Champion: 2014 Olympic Team Alternate: 2012


“[We] take the smaller unit away to competitions all over Europe, which we find essential. The horses have been free from coughs and nasal discharge, they are healthy and performing well.”

William Fox-Pitt, Team GBR Three Olympic Medals, seven World Championship medals



“It’s been a game changer. Havanna loves her hay, she’s eating well and she’s not having the allergic skin symptoms. She is shiny, well-muscled. It smells so good I want to eat it myself. It’s a fabulous machine that I can’t say enough good things about.”

Ashley Holzer, Team USA
International Dressage Rider, 4x Canadian Olympian, One Olympic medal

What the Veterinarians say

“We have used Haygain for foals with severe Rhodococcusequi pneumonia to aid in reducing the amount of inhaled allergens when they eat hay. We have also steamed bedding (ie: straw, not shavings) for the same reduction of potential inhaled allergens. For our colic surgeries that are not eating well, we have used Haygain to entice those horses to consume more roughage. The fresh aroma after the hay has been steamed appears to increase many horse's appetite postsurgery. I have first-hand experience with this product because not only do I use Haygain at my hospital, but for my own personal dressage and racehorses as well.”
Nathan Slovis

DVM, Dipl. ACVIM, CHT Director of the McGee Critical Care and Medical Center Hagyard Equine Medical Institute, Lexington, Kentucky

Well-known veterinarian Steve Engle, DVM suggests that all Margie’s horses start getting steamed hay as an all-around preventative measure for their respiratory health. [...] With more knowledge comes more awareness. In his view, inflammation throughout the horse’s body is the biggest performance limiter in otherwise sound horses. “This is what we seek to control in all aspects of health and disease and ultimately (and hopefully) improve performance in our sport horses.”
Dr Steve Engle, DVM
Equine Integrated Veterinary Solutions, NY, USA

"I am very happy with the results that I am seeing. One of my horses has had a dry cough for quite a while. I started [using] Haygain and within days [the cough] was gone. I can't wait to keep seeing the benefits of the Haygain.”
Sherry Cervi, USA World Champion Barrel Racing 4 Barrel Racing World Titles 3x WNFR Average Winner


"Luebbo had a little bit of a cough last summer. He'd cough once or twice when I started working him, then it would go away and come back. Ever since he's been on the Haygain, he hasn't coughed at all! I was shocked by how fast I saw a difference. His appetite has improved dramatically too [...]"
Jamie Barge, Team USA World Cup Finalist