Equine Urinary Tract Disease Study Guide

Overview and Clinical Importance

Urinary tract disease in horses is relatively uncommon compared to other species, with a reported prevalence of kidney disease at approximately 0.12%. However, horses possess unique urinary tract physiology that creates specific vulnerabilities to certain conditions. Understanding these diseases is critical for the NAVLE because when urinary problems do occur, they often represent serious, potentially life-threatening conditions that require prompt recognition and intervention.

Equine urine is uniquely alkaline (pH 7.0-9.0), high in calcium carbonate crystals, and contains mucoproteins from glands in the renal pelvis that give it a characteristic viscous, frothy appearance. This physiology predisposes horses to calcium carbonate urolithiasis and makes urinalysis interpretation different from other species.

Equine Urinary Tract Anatomy

The equine urinary tract has several unique anatomical features relevant to disease. The right kidney is heart-shaped (approximately 650g, 15cm long) and located retroperitoneally below the last 2-3 ribs and first lumbar transverse process, embedded against the liver. The left kidney is bean-shaped (approximately 600g, 18cm long), more caudal, and can be palpated rectally.