Dr. Emanuela Valle, a University of Turin veterinarian specializing in comparative nutrition, explains why it is important to provide steamed hay for healthier horses.
Emanuela Valle, EBVS® European Specialist in Veterinary and Comparative Nutrition, Dep. of Veterinary Science, University of Turin
An old saying goes “good hay half the dish,” but this is not enough for the horse’s health because the hay must not only be of high nutritional quality, but must also be healthy and wholesome.
Unfortunately, this is not always true, and especially in recent years there has been a significant decline in the quality of Forage dedicated to horses, either because of the scarcity of available product or because of haying difficulties that very often ruin the harvest. To address these issues, many stables have resorted to the use of pelleted or cubed forages, which, however, should not be a substitute for hay, but possibly a supplement.
So-called long hay, which in our stables is generally represented by first-cut hay, is a crucial food for our horse in order to promote gastro-enteric health and meet his innate foraging needs. Indeed, the horse needs to take adequate amounts of hay in its diet in order to be able to satisfy its digestive physiology, which in nature is based on long slow grazing. However, by spending many hours in consuming forage, the horse has a “breathing zone” where the concentration of irritants such as dust, mold, and endotoxins is very high. These are represented by gases such as ammonia found in litter and particulate matter such as dust and microorganisms (bacteria, yeasts, and molds) found in both litter and forage. These particles are very small (less than 5 µm) and therefore can be carried by inhaled air into the respiratory tree where they can settle.
In the stable, the horse spends a lot of time with its nostrils close to the ground and hay and as a result is highly exposed to respirable particulate matter, resulting in susceptibility to inflammation and irritation of the respiratory tract. In fact, the prevalence of respiratory disease in the horse is probably underestimated because respiratory tract disorders are detected only when they show obvious clinical signs such as coughing and nasal discharge.
The amount of particulate matter breathed in can be very high because, even at rest, the liters of air passing through the respiratory system are considerable: to make a simple comparison, at rest more than 70 liters of air pass through the horse’s airways while no more than six pass through the human airways. For this reason, the horse is very sensitive to air quality and irritants, including those contained in forage. Some horses are then more sensitive than others to these irritants and end up developing respiratory symptoms such as coughing.
Among the most frequent causes of coughing in young horses should definitely be mentioned IAD, or inflammatory respiratory disease, which often affects young horses, and the so-called bolsaggy or RAO acronym of the English description Recurrent Airway Obstruction which instead occurs in adult horses generally older than 7 years of age.
In both cases, the cornerstone of treatment is improved management that includes a decrease in the load of irritants and contaminants not only environmental but especially those that lurk in hay. In fact, it has been estimated that in the respiratory tree of 72% of horses suffering from IAD, fungi such as Aspergillus and Peniciullium, the same fungi found in forage, harbor. This means that these microorganisms that are often in hay can pass into the respiratory tract functioning as very dangerous irritants.
Horses that are sensitive to these substances are so even for very small amounts of particulate matter in hay, and exposure of allergen-sensitive individuals (especially molds) causes coughing to appear in a very short time between 5-48 hours. Suffice it to say that horses with RAO are prone to recurrent airway inflammation and broncho-constriction that can also occur very rapidly.
In both susceptible individuals and those predisposed to the development of IAD or RAO, but in any case in all horses, it is very important to therefore reduce the so-called load of respirable particles in the forage. When we consider that many of our horses in the stable then are sporting subjects, more than ever our goal must be to have a respiratory system that is functional and efficient and therefore not exposed to harmful concentrations of respirable particulate matter.
While there must be good air circulation in the stable and the bedding must be clean and dust-free, it must be said that we must always pay special attention to the quality of the hay.
However, wetting the hay is not enough; it has been proven that the traditional technique of “wetting the hay” is not so suitable for the horse’s health, but fortunately technology helps us with the use of steam produced by the hay-steamer.
Purifying hay is a strategy that can have a great impact on the health of all horses in general and for horses suffering from specific respiratory problems that are frequent in a horse’s career.
In wet hay, it is true that respirable particulate matter is reduced, but the microbial load of the forage is nevertheless increased. In fact, the longer the time the forage is left to soak in water, the greater the concentration of bacteria and yeasts; this is easily observed in hot weather when wet hay tends to take on an unpleasant odor precisely because of abnormal microbial fermentations. In contrast, with the use of steam produced by Haygain, not only are there beneficial effects on the decrease of respirable particulate matter but the microbial load is even reduced by up to 99%, making the hay healthier in all respects. In addition, soluble components, such as protein and minerals, are lost in the water used for soaking, thus losing an important part of the forage component. With the hay steamer, on the other hand, these properties are preserved and the forage is more palatable and of higher nutritional value.
The use of the Haygain hay steamer is the only scientifically proven method that substantially decreases the amount of inhalable particulate matter in hay and greatly lowers mold, fungal spores, and bacteria dangerous to the horse.
Thanks to its innovative technology, the Haygain performs a strong technological treatment against the potential irritants contained in the hay but, at the same time, gentle towards the noble nutritional component, such as soluble proteins and or minerals that are retained and not dispersed with the washing water. At the same time the hay becomes more palatable, as the heat releases from the forage the volatile aromatic components responsible for the typical fragrant odor much appreciated by horses. The hay after treatment stays healthy when stored in the appropriate container, facilitating stable operations. Clean hay is the basis of any horse’s management and is a boon in both allergic and sport horses where performance requires super work of the respiratory system.
Comparison of Haygain and hay water soaking
| Soaking in water | Haysteamer | Notes | |
| Respirable particles | ↓ ↓ | ↓ ↓ ↓ | |
| Microbial content | ↑ ↑ | ↓ ↓ ↓ | Haygain significantly reduces bacteria and mold content (up to 99%);10 minutes of soaking, on the other hand, increases it by 150% |
| Appetizability | = | ↑ ↑ | Haygain improves palatability |
| Nutritional value | ↓ ↓ | Loss of nutrients in the soaking liquid | |
| Production method | Long and tiring to handle with huge waste of water | Quick and easy | Haygain facilitates stable operations |
