There are differing reports about how many horses bleed after heavy exercise such as racing.

One can see bleeding from the nose after exercise in less than 1% of performance horses. But "scoping" or lung fluid samples suggest it is much more common.

Published and unpublished data suggests up to 60% of horses after hard work may show varying degrees of haemorrhage when the scope is passed into the bronchi.

Scientists now believe that the effect of massive lung pressures and/or lung infection many cause bleeding. From: Aust Equine Vet Vol 12(3) Aug 1994 and AJC Racing Calendar Jan 1995.

Work done by researchers at the University of California showed that the most important cause of "bleeders" is the high blood pressure in the lung (pulmonary) circulation of horses during very hard exercise.

Stress put on the horse's lungs is greater than those of any other athletic animal studied up to date. In "roarers" (laryngeal hemiplegia) the lung pressures are even greater. Try to partly block your nose and run 1-2km at the same time. You will feel the "extra pressures on your lungs" that we are talking about.

The amount of bleeding to cause a horse to "pull up" during a race is not known. The degree of discomfort bleeding causes to a horse in not known.

Bleeding into the lungs can cause severe and continuous "disease" changes. It should be taken much more seriously than has been the case to date.

Lung disease does not always lead to bleeding. Lung diseases are not very common to Australia, however the overall number of horses affected in Canada, USA and Australia does not differ that much.

Studies done by the University of Illinois showed that Lasix (furosemide) reduces blood pressure in lung blood vessels. This is backed up by clinical experience. Administration of this substance is permitted in many states in the USA. It works by making the body lose more water through urination.

The principle is simple:

More fluid = more blood = more pressure

Less fluid = less blood = less pressure

This provides a scientific basis for it's use in the treatment of bleeders. Furosemide belongs to the class of drugs called diuretics (they make you pee a lot) and is a prohibited substance under AR.117A.

In the journal "The Equine Athlete 1993 Vol 6. No3", under the heading of Stress fracture of pulmonary capillaries as mechanism for exercise-induced pulmonary haemorrhage; implications for management (JB West, O Mathieu-Costello, EK Birks, JH Jones, JR Pascoe and (WS Tyler), it has been demonstrated there is damage to the small pulmonary vessels (capillaries) which rupture under pressure.

Ranvet's Rutin Mix is a preparation of Rutin formulated to reduce the incidence of chronic cases.

Ranvet's Rutin Mix is a Bioflavonoid Compound to aid in the prevention and treatment of "BLEEDING" in racehorses, which has been caused by capillary blood vessel fragility and certain nutritional deficiencies. These compounds include Hesperidin and Troxerutin and have been claimed to increase the resistance of the capillaries and reduce their permeability to red cells.

Treatment: It is generally advised to commence using Ranvet's Rutin Mix immediately after a horse is found to "bleed" and continue using during spelling period, and for AT LEAST two months after training re-commences. If a horse is found to be particularly susceptible to "bleeding" attacks continue treatment on a daily basis throughout the animal's racing career.

Directions for Use: Mix the Rutin Mix thoroughly through the feed. Daily Dose Rates: 60g per day, a measure is included, one level measure holds 30g.Preferably split the 60g daily dose between the morning and night feeds.

Consult your Veterinarian if the condition does not improve.