What is bleeding in horses?
‘Bleeding’ in horses is a term for two related equine conditions: Exercise-Induced Pulmonary Haemorrhage (EIPH) and Inflammatory Airway Disease (IAD). EIPH results from a very high pressure in the pulmonary artery during intense exercise, and negative pressure in the alveoli (tiny air sacs within the lungs) at the same time as the horse breathes in. As a result of this, fragile pulmonary blood vessels in the lungs rupture, causing bleeding. Blood in the lungs and airways can lead to further bleeding as it acts as an irritant. IAD is described as mild to moderate Equine Asthma, affecting the lower respiratory tract and typically affects young horses, as early as one year of age.

Which horses suffer from bleeding?
Bleeding is seen most commonly in racehorses and other performance horses working at high intensity. However, numerous studies suggest that almost every horse has a varying degree of bleeding, but that only 5% would show blood at the nostrils. Other symptoms can include coughing, poor performance, taking longer to recover from exercise and more frequent swallowing. Most horses will swallow the blood and it will never be seen unless the horse is scoped. Due to the very small size of the blood vessels (the wall of these blood vessels is around 1/100th the thickness of a human hair) that rupture, most horses will only have a small amount of blood entering the airways. Horses most likely to see significant damage from bleeding in horses include those who do fast work regularly, those exercised on extreme surfaces – too hard and too soft, and horses carrying more weight. Having said that, research has also shown that horses doing moderate exercise (trotting and slow cantering) but over a long career can also show signs of bleeding. Repetitive exercise can have a cumulative effect on bleeding in the lungs which in some studies has been shown to worsen with age. From these causes, it is clear to see why racehorses are so affected by bleeding.

Why is bleeding in horses bad?
Apart from the fact that you don’t want your horse to be suffering at all, and therefore certainly not wanting to make them bleed, there are other reasons why bleeding has a negative impact. Bleeding will often go unnoticed where symptoms are not severe, but the most reliable way to check whether horses have EIPH or IAD is to scope the upper airway and trachea. Each time bleeding occurs, scar tissue forms in the lungs. Once an artery ruptures, it may become blocked or lose proper function. If it repairs, it will often be stiffer than previously, because damaged tissue is not as flexible as normal healthy tissue. As a result of this damaged tissue, the lung does not allow efficient gas exchange, leading to the horse having reduced lung function and capacity. This will obviously negatively impact performance and likely the speed and success of a racehorse. Additionally, for the small number of horses who bleed so much that it is not swallowed, and therefore appears at the nostrils, this can be fatal.
How can you manage EIPH?
As its name suggests, the related condition to EIPH called Inflammatory Airway Disease (IAD) is associated with inflammation of the airways. It has been found that haemorrhaging causes an inflammatory response rather than the other way round, however, any additional inflammation of the airways will only put more stress on the respiratory system and its ability to fully function. As a result of this, it is important to keep your horse away from any potential respiratory diseases, often caused by dust from their environment and the forage they eat.

The British Horse Feed’s Fibre-Beet and Speedi-Beet are both very good options for feeding these horses. These feeds are soaked fibre mashes which expand when soaked. These feeds are high in fibre and low in starch and sugar. As it is a beet pulp that is soaked before consumption, the horse is not exposed to any dust particles like they would be with a dry hard feed such as alfalfa. In addition to this, Fibre-beet can also be used to enhance or replace forage supplies (up to 60% of the daily forage allowance – for example, 1kg meal of soaked Speedi-Beet or Fibre-Beet could replace ½ kg of hay) when the other alternative might be very dusty forage. Like normal forage, these feeds should be fed in several, smaller feeds throughout the day, encouraging natural trickle feeding behaviour.
A 20kg bag of Fibre-Beet costs £19.09 – £20.09 and can be fed at up to 1kg/100kg body weight of your horse. The RRP of Speedi-Beet is £18.79-£20.79 and one 20kg bag will give you 125 Stubbs scoops, at just 15-16p per scoop.
Always consult your vet for any veterinary advice or get in touch with British Horse Feeds’ qualified nutritionists on 01765 680300.