1. Case Study
Urolithiasis

2. Signalment
20 year old APHA gelding
pink colored urine a!er exercise
intermittent colic episodes a!er
running and bucking

3. Normal Horse Urine is...
Cloudy
because horses excrete excess Calcium
Carbonate crystals via the renal system
Foamy
due to mucus secreted by the kidney that
prevents the crystals %om sticking together

4. What Causes a Stone?
Excess minerals
Diets high in Calcium or Phosphorus supersaturate the urine
Dehydration
Crystals are not kept in suspension and begin to stick together and form a stone
Infection
Bacteria acts as a nidus for stone formation
Genetics

5. When to suspect your horse has a stone?
Symptoms vary based on size and location of the stone
Difficulty or pain on urination
Frequent sma( urinations especia(y when ridden
Colic a!er exercise
Bloody urine
If the stone becomes lodges in the urethra and completely obstructs urine flow,
severe colic and death can result

6. Diagnosis
Urinalysis
blood in urine
increased Calcium Carbonate
Crystals
Pelvic Palpation and Ultrasound

7. Diagnosis
Urinalysis
blood in urine
increased Calcium Carbonate
Crystals 6 cm stone
Pelvic Palpation and Ultrasound

8. Diagnosis
Urinalysis
blood in urine
increased Calcium Carbonate
Crystals
Pelvic Palpation and Ultrasound

9. Diagnosis
Ultrasound waves hit the stone and bounce back
leaving a shadow below the edge of the stone
Urinalysis
blood in urine
increased Calcium Carbonate
Crystals
Pelvic Palpation and Ultrasound

10. Location of Bladder Stone

11. Treatment
Changing the pH of urine by changing the diet is not as successful for
horses as it is in humans and sma( animals
Most stones need to be surgica(y removed
Method of removal depends on size of stone
Perineal Urethrostomy - remove pieces of stone a!er %agmentation
with a laser
Celiotomy - abdominal approach to the bladder to remove entire
stone intact

12. Prevention
Consult with a veterinary to
ensure your horse is fed a
balanced diet with a correct
Ca:P ratio
Provide access to %esh water
at a( times