Last Updated on January 11, 2022
If your horse has had some medical tests, you will want to understand what the results mean. Your veterinarian might tell you that your horse has high levels of fibrinogen, but is this anything to worry about? And what does high fibrinogen mean in horses?
Understanding clinical tests is a complicated business, and it can be worrying when your veterinarian finds something like elevated levels of fibrinogen. Let’s find out what fibrinogen is and what high levels might mean!
What Is Fibrinogen?
Fibrinogen is a blood plasma protein generated by the liver. All mammals have fibrinogen, and it is an essential part of a healthy, functioning body system.
This tiny protein is one of thirteen factors required for normal blood clotting. When bleeding occurs, either internally or externally, the body starts a process called the coagulation, or clotting, cascade. It triggers these thirteen clotting factors to swing into action to stop the bleeding.
The role of fibrinogen in this process is to be first converted to fibrin and then form a fibrin-based blood clot. The aim of this clot is to seal up the source of the bleeding.
Fibrinogen also has some other useful functions in the equine body, and it regulates and moderates activities such as skin cell production and capillary formation. This means that fibrinogen plays an essential part in skin healing and repair.
What Is The Normal Range For Equine Fibrinogen Levels?
All horses should have fibrinogen, and without it, some serious problems could occur! A fibrinogen test is normally carried out alongside other routine screening tests, using a sample of blood. This means that a fibrinogen test can only be done by a veterinary professional.
The normal levels of fibrinogen in a horse are 2-4g/L (grams per liter). At certain life stages and fitness levels, this figure will vary. For example, the normal level of fibrinogen for a young Thoroughbred racehorse in training is just 1.5-2.3g/L.
If your horse’s fibrinogen levels are only slightly above or below normal, your veterinarian will advise you if this is anything to be concerned about.
What Does Low Fibrinogen In Horses Mean?
Luckily, low fibrinogen is not a common problem in horses. An adult equine can have levels as low as 0.3g/L without any significant problems.
In other species, low fibrinogen levels most often cause problems with blood clotting. This will normally only occur in horses with severe systemic diseases, such as septicemia. Some liver disorders can also cause low fibrinogen production.
What Causes High Fibrinogen In Horses?
Levels of fibrinogen increase and decrease according to the requirements of the horse’s body. If the horse’s body systems detect that more fibrinogen is needed, the liver will produce higher levels. When the body returns to normal, then fibrinogen production will decrease again.
When increased levels of fibrinogen production are triggered, the liver responds very quickly. A rise in fibrinogen would be detected within 24 to 48 hours of injury. Because of this rapid reaction, fibrinogen is referred to as an acute-phase protein.
If fibrinogen rises in response to an injury or inflammation, levels will double, triple, or even quadruple. It is not uncommon to see fibrinogen levels of 10g/L or above at the peak phase of infection. Your veterinarian may check fibrinogen levels several times to monitor whether it is increasing or decreasing.
Find more information What is a Warmblood Horse?
What Does High Fibrinogen Indicate?
The body triggers fibrinogen production if an injury or inflammation is detected. So, high levels of fibrinogen normally indicate that the horse has been injured or an inflammatory response occurring somewhere in the body.
The most easily identifiable reason for fibrinogen increase is an external injury. This will be easy to spot and hopefully easy to resolve! So, if your horse has sustained a large graze, laceration, or other types of wound, he may have raised fibrinogen levels.
Fibrinogen levels also rise in response to inflammation, which can be harder to pinpoint. Inflammation normally occurs in response to injury or infection. This can be internal or external and may affect the whole body or just a localized area.
So, your horse may have raised fibrinogen because of a systemic infection, such as strangles or Rhodococcus. The fibrinogen response could also be due to an internal abscess or parasite infestation.
This means that while fibrinogen is very good at telling us that injury or inflammation has occurred, it does not tell us where it is coming from! This is why other tests are normally carried out at the same time, to help pinpoint the reason why your horse has raised fibrinogen levels.
Learn more about What Is A Lame Horse?
How Do You Treat High Fibrinogen Levels In Horses?
The main objective in treating high fibrinogen levels in horses is to remove the source of injury or inflammation. This might mean that your veterinarian needs to carry out further tests to identify the problem.
If the raised fibrinogen is a result of injury, then this must be treated. The wound may be sutured, and a bandage used to reduce swelling. Your veterinarian might prescribe antibiotics and anti-inflammatory medication to reduce the inflammatory response.
For raised fibrinogen caused by infection or parasite infestation, the underlying cause must be treated. This means that your horse might need a course of antiviral or antibiotic medication or parasite control treatment.
In a situation where the cause of the raised fibrinogen cannot be identified, your veterinarian might advise that you treat your horse symptomatically. This means giving medication to reduce the inflammation.
It is very likely that your veterinarian will recommend testing for fibrinogen levels a few days after treatment has started. This will help to identify if the treatment is working, as fibrinogen levels should have started to decrease.
So, as we have learned, fibrinogen is a blood clotting factor that plays an essential role in hemorrhage control in horses. High levels of fibrinogen normally indicate recent infection or high levels of inflammation. Your veterinary professional will help you understand your horses’ blood test results in full.
We’d love to hear your thoughts! Does your horse have a history of high fibrinogen levels? Or maybe you have some questions about how to reduce inflammation in your horse? Leave a comment below, and we’ll get back to you!
Kate Chalmers is a qualified veterinary nurse who has specialized in horse
care for the vast majority of her career. She has been around horses since
she was a child, starting out riding ponies and helping out at the local
stables before going on to college to study Horse Care & Management. She
has backed and trained many horses during her lifetime and competed in
various equestrian sports at different levels.
After Kate qualified as a veterinary nurse, she provided nursing care to the
patients of a large equine veterinary hospital for many years. She then went
on to teach horse care and veterinary nursing at one of the top colleges in
the country. This has led to an in-depth knowledge of the care needs of
horses and their various medical ailments, as well as a life-long passion for
educating horse owners on how to provide the best possible care for their
Kate Chalmers BSc (Hons) CVN, Dip AVN (Equine) Dip HE CVN REVN RVN A1