Last November, the Eclipse Award winning top California Thoroughbred sire Bertrando was referred to the UC Davis Veterinary Medical Teaching Hospital (VMTH) with a history of repeated colic, fever and elevated liver enzymes. He was sent to UC Davis by River Edge Farm veterinarian Dr. Bill Stevenson because of the unusual nature of the horse’s symptoms and the possible serious consequences of liver disease.

Bertrando winning the Pacific Classic at Del Mar Racetrack in 1993.  Photo courtesy of 505 Farms

Upon admission to the VMTH, the stallion was assigned to the clinical medicine service and its staff of senior clinicians. Because of the peculiar nature of Bertrando’s symptoms and the rarity of liver disease in the horse, it was decided that the case should be managed as a team effort to ensure a thorough diagnosis and the best possible case management. Staff veterinarians Dr. Nathan Slovis and Dr. Betsy Carr were assigned to the daily monitoring of the case and senior faculty staff clinicians Drs. Gary Magdesian, David Wilson, John Madigan and Gary Carlson agreed to consult together on the diagnosis and treatment.

Following an extensive medical work-up and the completion of a wide array of laboratory tests, an initial diagnosis of cholangiohepatitis (inflammation of the liver and bile ducts) was made. Treatment with antibiotics, corticosteroids, fluids, antifibrotic agents and dietary therapy was administered and Bertrando’s initial response was quite good. However, the medical team was intent on determining the underlying cause of these unusual symptoms.

A liver biopsy was performed and the tissues sent to the VMTH’s histopathological laboratories for examination. The tests revealed that the horse’s liver was undergoing fibrosis (formation of scar tissue). It was also noted that the bile ducts were distended and enlarged. Liver problems such as these are usually caused by an obstruction of the major bile duct. Obstructions can be caused by such things as tumors or bile stones (similar to gall stones in humans). While gall stones are common in man, they are rare in horses because horses do not possess a gall bladder and their diet (herbivorous) usually does not lead to the production of stones. Biliary obstruction, whatever the cause, has grave consequences for the long-term health of the liver and, therefore, the life of the horse. Consequently, it was imperative to determine the cause of the suspected obstruction in Bertrando’s bile duct.

The breadth and depth of the VMTH medical team came into play to solve this unusual case. Specialists in ultrasonic imaging examined the liver to determine if there was a blockage of the bile duct. While the ultrasound examination determined that the bile duct in fact was obstructed, the cause could not be delineated. The cardiology department was called in to use its color flow ultrasonic imaging equipment. This highly sophisticated equipment is used to determine abnormalities of the circulatory system and in the blood flow through the heart. The images produced revealed an obstruction within the bile duct that appeared to be a stone.

Surgery to correct such a problem in the horse is extremely risky. Surgical access to the bile duct is not easy to obtain and it is very difficult to remove any obstructions and successfully reconstruct the bile duct. A review of the reported cases within the United States for this kind of surgery revealed that the survival rate in horses was very low. Consequently, the team felt that before attempting this risky surgery on Bertrando, it was necessary to obtain more information as to the nature and location of the obstruction to ensure the best chance for a successful outcome.