Normal equine gastroduodenal secretion and motility.

This research article provides an overview of the current knowledge and understanding regarding the secretory and motor activity in a horse’s stomach and upper part of the small intestine. It discusses the structure of a horse’s stomach, how acid secretion in the stomach is controlled, how the movement of stomach and duodenal contents is evaluated, and finally, the influence of certain movement patterns on fasting stomach contents.

Gastric Mucosal Anatomy in Horses

• The research first examines the structure of the horse stomach compared to other single-chambered stomach species. It places focus on the large non-glandular part of the horse stomach, discussing its function or potential lack thereof.

Control of Gastric Acid Secretion

• This section reviews how gastric acid secretion is regulated in horses. Acid secretion is evaluated by either collecting gastric contents from a cannula or by continuous pH measurement of said contents.
• The research underline the unhindered movement of contents between the stomach and duodenum. This movement can significantly impact the pH of the gastric contents.

Evaluating Gastroduodenal Motility

• Next, the authors discuss different methods for assessing movement within the gastroduodenal area, including monitoring of myoelectrical activity and changes in intraluminal pressure.
• Another method involves tracking the transition of radiolabelled contents from the stomach to the duodenum.

Influence of Gastroduodenal Migrating Motility Complex (MMC)

• The final part of the paper discusses the gastroduodenal migrating motility complex (MMC) and its impact on the composition of gastric contents during fasting.
• The research suggests that reflux of duodenal contents into the stomach is likely a regular event in horses, particularly during periods when antral motility is paused due to MMC.