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Target Publication: Barrel Horse News A horse turns the third barrel and heads back to alley. After crossing the timer and stopping at the alley gate, the horse coughs. The rider dismounts, the horse drops his head, and the rider notices a stream of blood trickling out the horse's left nostril. The rider, like many, is in "My first reaction was ok, call your vet, get him scoped and find out where it was coming from," 2009 NFR qualifier PJ Burger said. The horse experienced epistaxis, or bleeding out of the nostrils, the least common form of exercise induced pulmonary hemorrhage, commonly known as bleeding. Most of the time, blood is never seen within the horse's nostrils. However, according to the American Veterinary Medical Association over 80 percent of horses bleed after strenuous exercise. "For all those horses that you see a little blood at their nostril, there's hundreds of them that are bleeding that you don't ever see because most often the blood doesn't come out," said Todd Holbrook, Oklahoma State University Center for Veterinary Health Sciences associate In thoroughbreds, only around five percent show blood in the nostrils after performance, added the Equine Section chief specializing in internal medicine. "Bleeding goes on in the lungs, so ninety percent of the time you never see it even though they are doing it," Jim Chiapetta, equine veterinarian and co-inventor of FLAIR Equine Nasal Even if a horse is not bleeding from the nostrils, there are other signs indicating the horse is bleeding internally said Holbrook. Indicators of bleeding include reduced performance, slow or poor recovery, coughing, excessive swallowing and, possibly, even refusing the alley, under Holbrook explained, the only true way to diagnose the condition is to have a vet scope the horse within 30 minutes of performance or perform a bronchoalveolar lavage, or washing of the lung to obtain a fluid sample allows the vet to determine if there has been any blood in the lung, within a month of suspected bleeding. While the bronchoalveolar lavage is the most accurate way to determine if a horse has bled, according to Chiapetta, because it requires the horse to be sedated, scoping is the most "Over time, every instance of bleeding adds to that irritation of blood vessels so they're more vulnerable to bleeding next time," Chiapetta said. This is because bleeding causes inflammation of the horse's lower airway, he explained. Blood remaining in the horse's airway can also cause respiratory infections, since blood is an optimal environment for bacteria and organisms to grow. Burger noted after seeing a horse bleed, she likes to have a vet prescribe a round of antibiotics to ensure a lung or respiratory infection does not ensue. However, Holbrook cautions using antibiotics every time a horse bleeds. He added, while the risk of a horse getting an infection is real, so is the risk of complications, such as diarrhea, "Anytime you do something, you have to make sure you, above all, do no harm," the He advises evaluating antibiotic use on a per horse basis by looking at factors such as the distance the horse traveled in a trailer prior to bleeding and the degree to which the horse bled. After determining the horse is a bleeder, it is important to work to prevent bleeding from occurring in the future, explained Holbrook. Chiapetta noted, research has shown there is no method that completely prevents bleeding, however, there are several proven methods used to control it. "There're so many things on the market, some things work, and some things don't," said Burger. "Lasix is going to be your biggest thing. Your vets have some other potions and stuff they can give you, but I think Lasix is about the only thing that's going to prevent it." Both veterinarians agreed Furosemide, also known as Lasix, and FLAIR equine nasal strips are the only things clinically proven to prevent bleeding. Chiapetta also cited research done by Michigan State University demonstrating high doses of Omega 3 fatty acids fed over a three- month interval will reduce bleeding, but added there are no products on the market known to contain high enough levels of Omega 3 to prevent EIPH. Lasix, according to Chiapetta, is a diuretic that works by causing horses to urinate about 15 to 20 pound of water from their system. This causes their blood to drop in volume by Lasix is one of the top regulated drugs in the racehorse industry, he continued. The drug is administered about four hours before competition, and dosages vary depending on the severity of the horse's condition, the regulations of the state or competition, and the administering vet. "It's a fairly safe drug," Holbrook said. "I don't really worry all that much, even about the highest dose [10 cc] we administer or recommend administering. I believe that it's possible that lower doses [3-4 cc] could be effective in certain individuals, especially dependent on how severe their condition is and how hard that individual runs." However, he noted he tends to lean toward a more conservative, lower dosage when recommending the drug to patients. This is because there is a slight risk of dehydration that could increase if the horse is competing in a multi-run event, is in hot conditions or the horse is asked He suggested when using Lasix, electrolytes or salt should be added to the horse's feed to help prevent the horse from becoming dehydrated. Chiapetta noted studies have shown at low rates of speed Lasix reduces bleeding by about 70 percent, while the FLAIR nasal strips reduce bleeding by about 35 percent. However, when tested at high rates of speed, the FLAIR strips work as well as Lasix, both preventing bleeding "The strip works a great deal like human Breathe Right Strips at holding the soft tissue up and keeping nostrils open allowing the horse to breath," said Cody Hollingsworth, owner of the Western Integrity Agency the marketing firm for FLAIR strips. The strips work by supporting the soft tissue portion of the animal's nose, explained Chiapetta. When a horse is breathing hard, this area has a tendency to collapse because of intense pulling from the diaphragm as the horse is working to breathe. By supporting this area, it allows the horse to receive the oxygen it needs. Hollingsworth added FLAIR strips are a safer, drug free alternative to Lasix, and they are becoming more popular within the horse industry. Holbrook noted it is important for a horse to be examined by vet after bleeding to rule out other possible causes of the blood seen in the nostrils. However, he explained, by definition, if a horse has blood coming from its nostrils after exercise, the horse has EIPH. By taking steps to prevent EIPH, a horse is able to compete to the best of its ability, and the rider gets peace of mind from knowing they won't see their horse come out of a run with a distinctive, bright red trickle of blood from the horse's nostril. --------------------SIDEBAR---------------------------- The most commonly accepted of reason for bleeding, according to Chiapetta, has to do with a pressure differential created in the lungs during excitement. In the lungs there is a thin membrane separating the alveoli from the fragile capillaries, in which the red blood cells exchange carbon dioxide for oxygen that is transmitted back out into the body. He continued, a horse's spleen contains a high volume of blood, and the spleen releases some of its blood when a horse becomes excited. This increases the amount of blood within the Also, when a horse becomes excited, their heart rate rapidly increases pushing blood through the capillaries at a faster rate, Chiapetta said. This creates an area of high pressure on An area of low pressure is created on the other side of the membrane as the horse's diaphragm moves to pull in air, the vet explained. The pressure differential on the membrane causes it to rupture. Blood moves from the tiny capillaries into the alveoli in the lungs, and in extreme cases blood travels up the airways into the nose. However, both Chiapetta and Holbrook agree there are other theories for bleeding. A shift of the intestinal organs caused by the horse moving at speeds faster than a walk, has also been sighted as a potential cause of EIPH. Holbrook noted laryngeal hemoplegia, also known as roars and flappers, can cause restriction of the horse's airways. This causes the animal to work harder to breath, again creating a negative pressure differential on the membrane and causes the capillaries to rupture. ---------------------SIDEBAR----------------------------  Given intramuscularly or intravenously.  Administered four hours before competition.  Dosage: 3 cc to 10 cc, dependent on severity of condition.  Apply to horse's nose before competition.  Follow instructions provided in package to ensure strip is placed in the proper location.

Source: http://agcm3223.okstate.edu/12spring/allmon/portfolio/writing/the-red-flag.pdf