The SUCCEED Equine Fecal Blood Test is an antibody test that detects the presence of occult equine albumin and/or hemoglobin in a horse’s feces, indicating GI tract injury. A positive test result for hemoglobin represents a pathological condition that is producing whole blood somewhere in the horse’s GI tract.
What is Equine Hemoglobin?
Hemoglobin is a metalloprotein (metal cofactor, specifically iron) that is a component of red blood cells. Hemoglobin is critical to overall health and performance as its job is to move oxygen around the body. This becomes especially important when a horse’s job requires endurance. Because hemoglobin is the only way that muscle cells are oxygenated, an insufficient amount of hemoglobin can drastically affect performance.
The hemoglobin found in horse blood is unique to the equine species.
Hemoglobin is bound within red blood cells. Red blood cells are broken down when mixed with plain tap water (NOT salt water), releasing the hemoglobin and allowing it to be detected by the FBT.
Hemoglobin Indicates Injury in a Horse’s GI Tract
While albumin in a horses feces indicates a pathological condition specifically in the hindgut due to this protein’s degradation in the stomach and duodenum, red blood cells are more able to withstand the digestive process. Red blood cells, where hemoglobin is primarily contained, largely survive digestion in the stomach and small intestine. Some are degraded by bacteria in the hindgut, but the rest pass through into the horse’s feces.
Occult hemoglobin in a horse’s feces, therefore, may have originated from anywhere within the horse’s gastrointestinal tract.
Hemoglobin Only Produced by Bleeding Injuries
Because hemoglobin is bound up within red blood cells, it is only released from wounds with active vascular bleeding, or producing whole blood. This includes grade 2 or higher gastric and colonic ulcers, but not ulcers that are considered grade 1.
A Positive Equine Fecal Blood Test™ Result for Hemoglogin
If you have received a positive result for hemoglobin on the SUCCEED Equine Fecal Blood Test, the horse is suffering from active bleeding somewhere in the GI tract.
Potential conditions include but are not limited to:
- grade 2 or higher gastric ulceration
- colonic ulceration of a severity equivalent to a grade 2 ulcer
- gastritis or colitis with bleeding
- extreme parasitism where bleeding pits may have resulted
- endotoxemia, which may also have resulted from open lesions in the gut mucosa
- inflammatory bowel disease
Combining FBT results for hemoglobin with the accompanying FBT results for albumin indicate whether the hindgut and/or the foregut are involved.
Keep in mind that blood can be introduced into a horse’s GI tract from other sources such as dental work, rectal exams, mares in estrus, exercised-induced pulmonary hemorrhage, surgery and more. Be sure to keep all factors in mind and test accordingly.
Hemoglobin and Albumin Results Together on the FBT™
When results for albumin and hemoglobin are used together, veterinarians can determine whether the source of injury is in the horse’s foregut, hindgut, or both. Here’s what the combination of results shows:
- Positive for hemoglobin only represents a bleeding injury in the foregut only.
- Positive for albumin only represents a condition in the hindgut only.
- Positive for both hemoglobin and albumin indicates a definite hindgut condition, and a potential foregut condition.
- Negative for both hemoglobin and albumin generally indicates no hindgut condition, and no foregut conditions equivalent to grade 2 ulceration or higher. However, a subclinical foregut condition, such as a grade 1 gastric ulcer is still possible.
It is critical to remember that ulcers can bleed intermittently or, in severe cases where colonic tissue has died, won’t bleed at all. We recommend testing a horse multiple times with the FBT for the most accurate results.
Remember that the FBT does not provide a diagnosis. Veterinarians should always use FBT results in conjunction with the horse’s history, symptomology, and other diagnostics when evaluating digestive wellness or diagnosing health conditions and prescribing treatment.
