A blood test to identify the presence of stomach ulcers in horses is a step closer after researchers identified biomarkers linked to the disease.
Stomach ulcers are common in horses. They can affect the upper non-acid-producing portion of the stomach, where it is known as Equine Squamous Gastric Disease (ESGD), and the lower acid-producing glandular tissue, where it is known as Equine Glandular Gastric Disease (EGGD).
The current gold standard for diagnosing and monitoring stomach ulcers is gastroscopy, but it is not suited to screening as it is time-consuming and requires expensive equipment.
A less invasive and inexpensive method would be preferred, according to researchers.
Parichart Tesena and her colleagues focused their research on EGGD, which is the equivalent of peptic ulcers in humans.
The researchers noted that there were screening tests available – a commercial blood fecal test and sucrose permeability test – but their specificity is low and they cannot distinguish between ESGD and EGGD.
The study focused on five Thoroughbred horses aged 8 to 12 years with a history of lameness but no obvious gastrointestinal problems. The animals had a normal appetite, their feces appeared normal, and they had no record of any other sickness for more than two years.
The horses were given high doses of the nonsteroidal anti-inflammatory drug phenylbutazone (bute), which is often given for lameness, for two days. The dose was then reduced to conventional levels.
Gastroscopies showed that none of the horses had EGGD before receiving the high dose of phenylbutazone. All developed stomach ulcers in the lower acid-producing portion of their stomach as a result of receiving the drug. After treatment with omeprazole for a month, the stomach lining was repaired in all horses.
Blood was taken from each of the horses for analysis during the three phases of the experiment – before they were given phenylbutazone, during the phase when they had developed the ulcers, and a month after they had gone on to the anti-ulcer treatment.
The study team, writing in the Journal of Veterinary Medical Science, reported that their serum protein analysis identified 14 proteins that might be used as EGGD markers.
“However, confirmation of these candidate marker proteins is required with specific antibodies in the larger horse population before they can be considered for application in the field,” they wrote.
The study team comprised Parichart Tesena, with Chulalongkorn and Mahidol universities in Thailand; Yodying Yingchutrakul and Sittiruk Roytrakul, with the National Center for Genetics
Engineering and Biotechnology; Tuempong Wongtawan, with Mahidol University; and Kris Angkanaporn, with Chulalongkorn University.
Serum protein expression in Equine Glandular Gastric Disease (EGGD) induced by phenylbutazone
Parichart Tesena, Yodying Yingchutrakul, Sittiruk Roytrakul, Tuempong Wongtawan and Kris Angkanaporn.
J. Vet. Med. Sci. 81(3): 418–424, 2019 doi: 10.1292/jvms.18-0679