Is your hay clean enough?
In Ireland, forage is the foundation of every horse’s diet. But even hay that looks good can present hidden risks: dust, mould spores, and bacteria that can cause respiratory issues, trigger coughing, and even reduce feed intake. For many horses, hay steaming can be extremely beneficial as a way to help alleviate respiratory conditions, whilst also improving palatability and reducing hay waste.
1. The Hidden Risks in Hay
Even the cleanest-looking bale of hay can contain high levels of dust and microbes. Studies have shown that up to 88% of hay sampled across Europe contains potentially harmful levels of dust, mould, or bacterial spores (Moore-Colyer et al., 2016). In Ireland, where weather conditions often lead to suboptimal curing and storage, the risk is even higher.
In some horses, breathing in these microscopic allergens can trigger an inflammatory reaction in the small airways of the lung, resulting in mucus production and constriction of the air passages. This causes clinical signs such as coughing, wheezing, nasal discharge and respiratory-related poor performance. The severity of these signs will vary from horse to horse, but in some animals the decline in respiratory health can prevent the horse being used for athletic pursuits. The veterinary world has used several different names for this condition over the decades, but now the term Equine Asthma is accepted as best reflecting the basis of the disorder.
2. What Steaming Actually Does
Unlike soaking (which reduces dust but can promote bacterial growth), hay steaming uses controlled high temperatures to penetrate the hay and eliminate contaminants. Devices like the Haygain hay steamer reach internal hay temperatures above 100°C, which is proven to kill:
• Mould spores
• Fungal hyphae
• Bacteria including Actinobacillus and Streptococcus species
In a 2018 study by Moore-Colyer & Fillery, hay treated in a Haygain steamer showed a 99% reduction in airborne particles, along with a significant drop in Aspergillus fumigatus, a common trigger for inflammatory respiratory disease in horses.
3. Palatability: An Additional Benefit
Aside from hygiene, hay steaming dramatically improves the smell and taste of forage. Horses often prefer steamed hay, especially those recovering from illness, older horses with dental issues, or fussy eaters. The improved palatability of steamed hay leads to
• Increased feed intake
• Reduced hay waste
• Better hydration from the added moisture from steam.
This is particularly useful during stressful periods (e.g., transport, competition, hospitalisation), where appetite may already be compromised. Steamed hay is also consumed more slowly than dry hay, increasing the time spent feeding. This helps maintain stomach fill and saliva production, both of which reduce the risk of gastric ulcers.
4. Who Should Use Hay Steamers?
While hay steaming has traditionally been used in high-performance and veterinary settings, it is increasingly recognised as valuable for all horse owners, especially those managing:
• Horses with a history of coughing or respiratory issues
• Horses stabled for long periods
• Horses exposed to poor-quality or dusty hay
Summary
Hay steaming offers a practical, science-backed way to improve both the hygiene and palatability of forage. Backed by extensive peer-reviewed research and supported in clinical and stable settings worldwide, this technology is an important tool in the daily management of equine health.
By reducing respiratory risk, improving feed intake, and decreasing waste, hay steaming contributes meaningfully to both welfare and performance—making it one of the most valuable advances in modern horse care.
________________________________________
Explore the Haygain range at www.ark-equine.com/haygain
