Enteric neuropathy in horses with grass sickness.

This research examines the degeneration of enteric neurones in horses with grass sickness, a deadly disease that causes severe damage to the nerves of the gut. The study explores the distribution of the lesions throughout the gastrointestinal tract and their potential link to the severity of the disease’s symptoms.

Study Methodology

• The research team took samples from 11 different sites along the gastrointestinal tract of several horses. This includes eight control horses not suffering from any gastrointestinal disease, five horses with acute grass sickness, and three horses suffering from chronic grass sickness.
• The researchers then examined these samples under a microscope to understand the organization of the enteric ganglia in these animals, comparing it to those found in other large mammalian species.

Key Findings

• The study found that all the horses suffering from grass sickness had severe enteric neuropathy. This damage was found throughout the gut in acute cases but was localized to the distal small intestine in cases of chronic grass sickness.
• Minor exceptions were observed, such as the presence of nerve cell bodies in the fundic mucosa and blood vessels within the submucosal ganglia.
• The severity and widespread nature of the enteric neuropathy found in the affected horses aligns with, and could potentially explain, the persistent and severe gastrointestinal propulsion deficit that is a hallmark of grass sickness in horses.

Conclusions and Implications

• The results of this research provide valuable insights into the nature of grass sickness in horses, particularly in terms of its impact on the gut’s nerves. Understanding the distribution and severity of lesions may help to better understand the varying symptoms and progression of the disease.
• More broadly, the study contributes to our general knowledge of enteric neuropathy as it occurs in large mammals, thereby aiding in disease prevention and treatment efforts.