What Are the Causes of Kidney Failure in Horses?

Kidney failure is rarely seen in horses. It is so rare, in fact, that there is not really a market that caters toward long-term sufferers. In most cases of kidney, or renal, failure in horses, the animal is so sick it does not recover. But in some cases, acute renal failure can be stopped, and chronic renal failure can be slowed.

  1. Symptoms

    • In most cases, kidney failure is not something that is noticed quickly. The horse may drink significantly more water. The appetite might be reduced. The animal may appear lethargic and weak. The animal may urinate more frequently, and the urine might be dark, in some cases as dark as blood. The horse may eat copious quantities of salt if it is available. If any length of time goes by and the kidneys are failing, all these symptoms will worsen, and the animal will visibly lose condition.

    Dehydration

    • One of the main causes of kidney failure in horses is dehydration. When a horse does not have enough fluid in its body to maintain good blood pressure, the blood is not circulated properly, and toxins build up in the blood stream, causing organ damage and failure. Be it a case of no water, no intake, heatstroke or diarrhea--if the animal gets dehydrated, the kidneys can be damaged within hours.

    Toxins

    • If the horse has ingested even small amounts of plants with natural toxins in them--such as snakeroot, bracken fern, withered red maple leaves or onions--the toxins released during digestion can effectively kill the kidneys. In most cases, horses will avoid these plants, but in the case where there is nothing else to graze on, or if the animal has spent most of its life in a stall and is not "educated," it can and will eat these plants. So it is best to check your pasture area for them.

    Shock or Injury

    • In the case of shock or a severe wound with massive blood loss, the kidneys can be damaged by the lack of blood flow to the organs. When the kidneys are not pumping the blood, toxins are building, and the sensitive tissues of the kidney itself are being damaged. Anything that interrupts blood flow is a danger to renal function.

    Colic

    • When a horse colics, its entire system is sent into chaos. The digestive system, so critical to the life of the animal, shuts down, and toxins build immediately. Clots can form in the blood, which can then block the kidneys. The additional toxins in the blood from the illness cannot be filtered, and the kidneys become damaged.

    Treatment

    • Only a professional veterinarian can test the horse to see what type of damage there is and how badly the horse's kidneys are damaged. In the case of mild damage, there may not be any treatment necessary. In the case of severe damage, euthanasia is the most humane option. Electrolyte therapy, diet restrictions and I.V. treatment may or may not be helpful. The veterinarian will be able to determine what, if anything, can be done long-term for a horse with kidney damage.