The cause of urinary bladder stones in horses is believed to be in part due to diet. Horses consuming diets high in calcium such as alfalfa and drinking water that has a high calcium content may be predisposed to developing urinary bladder stones. However, the condition is relatively rare when one considers how many horses are fed a pure alfalfa diet! In addition, horses can develop stones in the bladder AND kidneys. These stones may travel and lodge within the ureters and the urethra. In my clinical experience, I have diagnosed urinary bladder stones in 2 geldings and 1 mare. In addition, I have diagnosed kidney and ureter stones in 2 geldings and 2 mares. If the stones obstruct the flow of urine from the kidneys into the urinary bladder they will ultimately result in compromise of kidney function. Common clinical signs include increased urination, increased water intake, recurrent low-grade colic, fever, blood in urine, and poor performance.