Wrong. Cushing’s disease and laminitis like to go hand in hand. PPID
horses, even when well managed, can
still be at increased risk of developing laminitis due to their altered
metabolism and its effect on the
extremely delicate sensitive laminae,
the structure within a horse’s hooves
that keeps the coffin bone suspended
within the hoof capsule.
PPID horses are also at higher
risk for infections. Regular farrier
visits and close inspections of any
nicks or scrapes are some of the
best ways to stay vigilant when
looking out for long-term health of
ANNA O’BRIEN, DVM, is a large-animal
ambulatory veterinarian in central Maryland.
Her practice tackles anything equine in nature,
from Miniature Horses to zebras at the local
zoo, with a few cows, goats, sheep, pigs, llamas, and alpacas thrown in for good measure.
5. Can’t prevent it, but…
As researchers haven’t yet discovered an extrinsic reason as
to why some horses develop Cushing’s disease and others
don’t, the condition isn’t currently viewed as preventable.
Additionally, it’s important for horse owners to understand
that there isn’t a cure for this disease; once diagnosed, a horse
will require lifetime medication and dietary management to
take control of the disease.
However, it’s not all bad news. With the proper medication
at the right dose, monitoring, and other changes as needed,
this disease can be very successfully managed so that horses
with PPID aren’t suffering.
6. There is an approved drug for it.
In 2011, the drug Prascend (pergolide mesylate) was approved by the FDA for the control of clinical signs of PPID in
horses. This is the gold standard management medication for
this disease and it comes as an oral tablet.
Not every horse with PPID will require the same amount
of Prascend; your veterinarian will start your horse on a set
regimen and then tailor the dosage based on your horse’s
response to the medication.
Typically, horses with PPID will experience resolution of
clinical signs such as hirsutism (a long, shaggy coat that does
not shed) and excessive drinking and urinating within six to
eight weeks of starting the medication.
7. Stereotypes sometimes don’t fit.
Many horse owners may be aware of the stereotypical Cushing’s horse: old, thin but
with a potbelly, and a long hair coat that does not shed out in the summer. These
horses might as well have a neon arrow pointing at them that says: “Cushing’s!”
But, not all Cushinoid horses will appear this way. Remember that this condi-
tion is a result of overactive cells in the pituitary gland. Not all horses will have
the same level of over-activity, and younger horses may only have subtle clinical
signs that may manifest in nebulous or inconsistent ways.
A thorough physical examination and diagnostic blood tests performed by your
veterinarian are a must for proper and timely diagnosis of this condition, especially
in younger horses, where the stereotype may not apply.
8. One disease can look like the other.
Equine metabolic syndrome (EMS) is another complicated endocrine disorder
in horses, involving insulin resistance and laminitis. Oftentimes, clinical signs of
muscle wasting and abnormal fat deposits are seen in both EMS and PPID and,
to make matters even more complicated, some horses can have both conditions.
Diagnostic blood tests can differentiate the two diseases and both can be managed simultaneously. Fortunately, nutritional management such as a reduction
in certain carbohydrates such as starches and simple sugars can be used in both
conditions to help control clinical signs.
9. Remaining vigilant is the key to success.
So your horse has been diagnosed with PPID, and your vet has him on a medical
management regimen that appears as though it’s working. All done, right?