Ask the Vet: The Pre-Purchase Examination

Are you considering purchasing your first horse or growing your existing herd? Don't forget the pre-purchase examination! Pose these questions for our month's AAEP expert, Dr. Kerry Beckman.

Question: Does a capped hock have a lasting effect on a horse's physical performance that may be used for racing?
A capped hock is a distension of a bursa (fluid-filled sac) at the point of the hock. This is usually the result of an injury to the area, or the horse repeatedly kicking the stall wall. 
An uncomplicated capped hock is considered to be only a cosmetic problem for the horse, and will not affect athletic performance. However, if there are underlying complications, such as infection or damage to nearby bony or soft tissue structures, there may be a detrimental effect on performance. 
When purchasing a horse with a capped hock, I recommend having the area evaluated by radiography and ultrasonography to ensure there are no other lesions present.
Question: I am looking at a horse to purchase. He is HYPP N/H. What special considerations should I look at as he has never had an episode and is now 6-years-old? What are the chances that he will? I am looking at this horse for a 10 year old rider.
Possible results of HYPP testing are N/N ("double positive"), N/H ("heterozygous"), and N/N ("normal").  N/H horses are also referred to as HYPP "carriers," because they carry the disease in their genes, but they don't always exhibit symptoms. Usually, a horse will shows signs of HYPP during the first few years of life, especially when training is intense. However, there are documented cases of horses showing signs of their first HYPP attack late in life. There is no way to predict if a N/H horse will show signs of HYPP during its lifetime.  
I recommend that all American Quarter horses be managed as if they have a tendency toward having HYPP attacks. Dietary management is extremely important in the management of affected horses. Dietary adjustments include (1) avoiding high potassium feeds such as alfalfa hay, brome hay, canola oil, soybean meal or oil, and sugar molasses and beet molasses, and replacing them with timothy or Bermuda grass hay, grains such as oats, corn, wheat and barley, and beet pulp; (2) feeding several times a day; and (3) exercising regularly and/or being allowed frequent access to a large paddock. If an attack has been documented, treatment of the horse with acetazolamide (under veterinary supervision) can also be helpful.  
You are wise to investigate the potential health problems of a horse before you purchase it. You may also consider screening the horse for other genetic diseases. The American Quarter Horse Association (AQHA) is now offering a five-panel genetic disease screening test through the University of California, Davis (UC Davis), Veterinary Genetics Laboratory, according to a statement on the organization's website.
The test will screen for five potentially fatal genetic diseases often found in Quarter Horses:

Glycogen branching enzyme deficiency (GBED);
Heredity equine regional dermal asthenia (HERDA);
Hyperkalemic periodic paralysis (HYPP);
Malignant hyperthermia (MH); and
Polysaccharide storage myopathy (PSSM).

The five-panel test will cost $85 for AQHA members and $125 for nonmembers, the statement indicated. Interested parties are asked to call the AQHA at 806/376-4811 to secure their test.
Question: I am buying a horse and a lameness exam seems a waste of money. What is really important to know and tests be taken when considering adopting a horse? (adoption as a family member). I am about to buy an 8-year-old that moves very well. What are the hidden considerations?
A thorough pre-purchase exam is an important part of buying a horse. For most equine practitioners, the lameness portion of the exam is only a small part. The horse should be examined from nose to tail, including the eyes, heart, lungs, oral cavity, skin, and musculoskeletal system. This "vetting" is crucial to help you decide if the horse will be a suitable match. There are numerous diseases that can be detected during the exam, as well as lameness issues that would limit the horse's performance. Also, the health of the horse should be evaluated to ensure that you are not bringing a contagious disease into your current herd. The monetary cost of the pre-purchase exam is minimal compared to the potential veterinary costs of treating the horse once you own it. Even a free horse can incur substantial veterinary bills over its lifetime, and it would be wise to approach the acquistion of a new horse with the most information possible.