A Horse & Hound Podcast promotional feature with Dengie
Welcome to the first part of a two-episode Horse & Hound Podcast promotional feature with Dengie. Horse & Hound’s podcast host Pippa Roome chats to Dr Michael Hewetson, an associate professor of equine internal medicine at the Royal Veterinary College, and Dr Katie Williams of Dengie, about the different types of gastric ulcer that horses can suffer from, how to recognise the signs, and how to confirm diagnosis, as well as treatments and management techniques.
You can listen online here or via your favourite podcast app.
Over the past decade, studies have increased our awareness and understanding of equine gastric ulcer syndrome, but there is still much to learn. We know there are two distinct diseases which affect different areas of the stomach: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). While there are recognised causes and management regimes for ESGD, less is known is about EGGD.
Dr Michael Hewetson explains: “One of the major paradigm shifts in our understanding of this syndrome over the past 10 to 15 years has been recognising that under the umbrella term of equine gastric ulcers syndrome are two very distinct distinct diseases, which relate to where the pathology lies anatomically within the stomach of a horse. People need to understand that their horse’s stomach is very different to our stomach, insofar as it’s got two very distinct different layers to it.
“In the upper portion of the stomach, the lining is what we call squamous epithelium. It’s a specific type of cell that forms that layer. And in the lower part of the stomach, it is a very different lining or epithelium, that’s called a glandular epithelium. It’s those key differences in the anatomy of the stomach that results in two very, very different diseases depending on where we see the pathology.
“So if we start with the disease that’s best recognised and most widely reported in the literature, that’s squamous gastric disease which affects the upper portion of the stomach and specifically affects the squamous epithelium. This is a very, very common disease, particularly in performance horses and it’s often related to the intensive management of horses kept as performance animals, and their associated nutrition, including high starch diets with a lack of roughage, in addition to intense exercise. These are all factors which increase the likelihood of acid splashing up from the lower part of the stomach into this squamous epithelial part of the stomach.
“In a normal horse, the upper portion of the stomach is not exposed to an acidic environment. They eat roughage throughout the day which forms a mat that lies on top of the acid secretions of the lower part of the stomach and protects the upper part of the stomach from acid injury. If you look at a pH graph of acid in the stomach you’ll see that in the lower part of the stomach pH is very low, around about two, and then by the time you get to the upper portion of the stomach, the pH is increased up to about six. So if you have management factors that predispose a horse to squamous gastric disease, they start to get acid injury of this area of the stomach and that results in ulceration, which we recognise as equine squamous gastric disease.”
