Sarcoids are the most common tumour that occurs in horses. They are locally invasive, and difficult to deal with because recurrence is common even with aggressive therapy. One study showed that 14% of sarcoids occur exclusively in the periocular region (near the eye), and these tumours can be particularly tricky to deal with as it is difficult to get good margins to remove all tumour cells during surgical excision.

Pituitary pars intermedia dysfunction (PPID) is an endocrine disease that is thought to affect between 15-30% of aged horses. The most obvious clinical sign in more advanced cases is hypertrichosis (hair growth, abnormally long curly hair, and/or a failure to shed out normally in the summer). Other clinical signs can include increased drinking and urination, chronic infections, muscle wasting, weight loss, regional fat deposits, and an increased propensity to develop laminitis (founder). Because this disease occurs in older horses, it is often missed as the owner assumes that their horse isn't looking and feeling as well merely because they are getting older. The following is a report of one case in a horse used for competitive polo, written by her owner Connie:

Dr. Kirby Penttila dicusses diagnostic imaging as it relates to the lameness examination.

Dr. Crystal Lee performs a live demonstration of the Lameness Locator.

Dr. Crystal Lee discusses objective lameness evaluation using wireless inertial sensors.

Dr. Alyssa Butters discusses the typical progression of a lameness exam.

This excerpt is part 1 of 4

Part 2 - The Lameness Locator

Part 3 - Lameness Locator Demonstration

Part 4 - Imaging

Sugar sustained a major laceration to the front of her carpus during the big snowstorm we had in September 2014. Even though her owner found it the day it happened, there was already a large amount of swelling present as well as a large amount of dirt and contamination in the wound. Initial treatment included intravenous regional limb perfusions with antibiotics, intravenous antibiotics, and bandaging. Because of the large amount of motion present on the front of the carpus, we ultimately decided to use pinch grafts in this wound. Pinch grafts are small 3mm discs of skin, harvested by removing an elevated cone of skin, that are implanted into small slits in the granulation tissue.

In horses, the third eyelid is prone to developing squamous cell carcinoma. Squamous cell carcinoma is the second most common tumour in horses, and it is the most common tumour in the equine eye. It develops most commonly on areas lacking pigmentation, poorly haired regions, and skin near mucocutaneous junctions. It can be quite an aggressive tumour, spreading to nearby tissues and local lymph nodes. In the third eyelid, it often initially appears as a reddened area, then becoming raised and in some cases developing a wart-like appearance. In most other areas, recurrence is extremely common unless surgical excision is combined with another treatment such as chemotherapy or cryotherapy. Fortunately, the third eyelid can be removed in its entirety, and a success rate of 90% has been reported with removal alone.

Understand Your Horse’s Vision and Common Eye Disorders. Written for the Canadian Horse Journal’s July 2015 issue.

                Just as in humans, most vaccinations cause at most very mild outward symptoms after the vaccine is given.  Some horses may be a little more lethargic than usual, have some mild tenderness at the injection site, or stiffness in the neck if that is where the vaccine was administered.  Occasionally, the horse will develop a mild and transient fever, and this is usually noticed if the horse goes off his feed.  These usually resolved uneventfully, although sometimes anti-inflammatories are given.

     With several recent outbreaks of neurological herpesvirus infections in the US and Canada, much attention has been turned to this common disease.  The virus is not new, and is considered endemic in most regions of the world.  Although some aspects of the disease have been understood for decades, there is still much to be learned about the virus and its effects on horses.

Both horses and humans are very susceptible to tetanus, horses even more so than humans.  In humans, there are many studies examining the duration of immunity following vaccination, so physicians can feel confident in their recommendations of extending the revaccination interval.  In horses, a 6 month study comparing responses to commercial vaccines demonstrated significant antibody response for the duration of the study, but did not measure the response beyond 6 months.  There have not been any studies in North America that have challenged vaccinated horses with tetanus toxoid, but antibodies alone can mediate protection.  Conclusions about efficacy of the vaccine and duration of protection are based on antibody levels detected in laboratory studies combined with field experience, and the recommendation for yearly vaccination stems from this. There have been rare reports of horses with clinical cases of tetanus that had been vaccinated, however survival of horses with tetanus is strongly associated with previous vaccination.