Frank M. Andrews, DVM, MS, DACVIM

Colic cases

Equine Cushings Disease (Pituitary Pars Intermedia Dysfunction [PPID]) is a disorder that likely affects more than half the population of horses aged 14 years and older. If unmanaged, affected horses are at risk for laminitis and insulin resistance (IR) and are immune-suppressed, increasing their risk of numerous infections.

Fermentation in the hindgut of the horse is similar to that in the rumen, resulting in the production of short-chain volatile fatty acids mainly acetic, propionic and butyric acids. The proportions of these acids are influenced by the availability and type of substrate, composition of the microbial community and the hindgut physiologic conditions.

Equine gastric ulcer syndrome (EGUS) is common in performance horses and in foals. Diagnosis of EGUS is based on history, clinical signs, endoscopic examination, and response to treatment. All ages and breeds of horses are susceptible to EGUS and current therapeutic strategies focus on blocking gastric acid secretion and raising stomach pH.

Deciding when to refer a horse with colic can be a difficult decision and involves careful evaluation of clinical and laboratory parameters, surgical considerations, probability of survival, and other considerations that include worsening of clinical condition, unresolved pain, or to obtain a second opinion.

Unlike EGUS, colonic ulcers and the condition Right Dorsal Colitis (RDC) occur less frequently, but may lead to hypoproteinemia and more severe clinical signs. In a necroscopic study of 545 horses, 44% of non-performance horses and 65% of the performance horses had colonic ulcers.