Diabetes Mellitus in the Horse: a Case Report and Review of the Literature

Abstract

SUMMARY This paper records the clinical and postmortem findings in a mare with diabetes mellitus. The main features were rapid emaciation, abnormal glucose tolerance and no response to insulin. At postmortem examination a tumour of the pars intermedia of the pituitary, adrenal cortical hyperplasia and depletion of the β cells of the pancreatic islets were the principal findings. The literature on this syndrome in the horse has been reviewed. RÉSUMÉ Cet article donne un compte rendu clinique et nécrop‐sique d'un cas de diabète sucré chez une jument. Les signes principaux étaient un amaigrissement rapide, une tolérance anormale au glucose et l'absence de réponse à l'insuline. A l'autopsie on a trouvé une tumeur de la pars intermedia de l'hypophyse, une hyperplasie du cortex surrenal et une déplétion des cellules beta des ilots pancréatiques. Une revue de la littérature est donnée. ZUSAMMENFASSUNG Dieser Artikel beschreibt die klinischen und pathologischen Befunde bei einer Stute mit Diabetes mellitus. Die hervorstechenden Symptome bestanden in rascher Abmagerung und Entkräftung, in einer abnormen Glukosetoleranz und einer fehlenden Reaktion auf Insulin. Bei der Autopsie fand sich ein Tumor der pars intermedia der Hypophyse, eine Hyperplasie der Neben‐nierenrinde und eine Verminderung von β‐Zellen in den Pankreasinseln. Die Literatur über dieses Syndrom beim Pferd wird besprochen.

Diabetes, Insulin Resistance, and Metabolic Syndrome in Horses

“…27 A few cases of bona fide DM have been reported to develop in adult horses. 28,30,[36][37][38][39][40][41][42][43][44] Specific causes for DM that have been described in horses have included chronic pancreatitis, [36][37][38] ovarian neoplasia, 39 pregnancy, 30 and immune-mediated polyendocrinopathy. 40 Transient DM was also identified in a 3-day-old foal that presented with diarrhea.…”

Equine pancreatic disease

“…While the cause of the pancreatitis was not specifically known, it was considered to be a result of the concurrent diabetes mellitus, a condition that, in dogs, is associated with the development of pancretitis. 1,6 All 4 cases in the current study presented with colic, and while 2 had other reasons for gastrointestinal colic, acute pancreatitis often presents with marked abdominal pain, gastrointestinal reflux, and hypovolemic shock. 22 Chronic cases are more likely to show weight loss, inappetence, lethargy, and mild to recurrent signs of colic.…”

Spontaneous Diabetes Mellitus in Animals

“…Supplementary, the animals present bad condition of hair coat (bilateral alopecia) and skeletal muscles, excessive fragility of the skin, enlarged abdomen (pot belly), bacterial infection of skin, urinary and respiratory tract [64]. ACTH secreting adenoma of pars intermedia associated with hyperplasia of adrenal cortex and reduced -cell population was diagnosed in horse, although reference to hormonal antagonism is not discussed [105].…”

“…Diabetes mellitus was diagnosed in horse and pony, all cases being described in individuals with pancreatitis or pars intermedia pituitary tumors [11][12][13]. IDDM was reported mainly in young horses, but elderly horses are also affected (the age ranges between 5 and 18 years).…”