PPID / Cushings Info

Found your self with a Cushings equine? Or suspect it? Or wondering what the red flags are for PPID in your horse?

WHAT IS PPID?

PPID aka Equine Cushing’s is on the rise, or perhaps more is known about it, being recognized and the cause is being able to be treated. PPID is a progressive disease which cannot be cured and symptoms will progress as the equine ages. The great news is that medication is available to help stabilize the cause of the PPID. PPID is one of the most common diseases of horses greater than 15 years of age. Abnormally high hormone (ACTH) levels in the blood, along with other hormones and cortisol play big roles in this disease. Its official name being Equine Pituitary Pars Intermedia Dysfunction (PPID) because it refers to the location within the brain that is abnormal. The pituitary gland is located at the base of the brain. In horses with PPID, the middle lobe of the pituitary gland (pars intermedia) becomes enlarged over time and results in over production of hormones. The growth of the middle lobe of the pituitary gland can compress the adjacent structures in the pituitary and hypothalamus resulting in loss of their function. 

WHO DOES IT AFFECT?

PPID is not just restricted to fat hairy little ponies, it can affect ANY equine, ANY age although the most commonly affected are horses 15 years and over, commonly in their 20's. The classical and most obvious outward signs of PPID are muscle wasting, sagging abdomen and a long, often curly coat that does not shed normally. However, these symptoms are relatively late in the course of the disease and PPID can be present for many years before they are seen.  

WHEN IS IT COMMON FOR THINGS TO GO WRONG?

ACTH, adrenocorticotropic hormone, is produced by the pituitary gland. Its function is to trigger cortisol release from the adrenal gland. Cortisol in turn causes insulin resistance. This can result in an unexpected case of laminitis, often the first of the horse’s life. Every year in autumn there is a temporary increase in the amount of ACTH produced in all equines. For most horses this is a relatively small increase and does not cause any problems. However, for horses in the early stages of PPID, it can mean disaster.  Your horse suddenly "gets laminitis" but has "never" had it before.  Your horse gets laminitis in autumn - all very HUGE red flags that all is not well.  Studies indicate that 95% of laminitis cases have an underlying metabolic issue - PPID, IR or EMS.

**It’s important to understand the laminitis and other changes can only be controlled by removing the cause – the high ACTH. That is what the PPID medication does. No amount of diet manipulation, supplements or anti-inflammatory drugs is going to make a difference if you don’t address the root cause.**

EARLY SYMPTOMS

These are some of the ‘Not Quite Right’ things to watch for in younger horses (i.e. 10 and over) that may point to early PPID/Elevated ACTH levels, as collated by a group of vets overseas. Gradual changes are easy to write off as being their new normal especially as the equine ages. Individually these may be due to another cause but if you get more than one, it might be time to be pro-active and test ACTH. It is also possible that the horse only has irregular ACTH during the seasonal rise. Many owners find that, after diagnosis, they could see that the slow changes had started a few years prior. This may help to pick up on them early as will routine annual testing after the age of 10.

Early potential indicators of developing PPID:

Anhydrosis; Failure to sweat or reduced sweating. 

Unexpected sweating. Eg. Lathered between the hind legs after a short walk. 

Lots of sweat on a hot day, compared to herd mates.

Thermoregulation; Horse was shivering at 13C on a showery, windy day where the ‘feels like’ temp was about 9C. He wasn’t usually rugged unless it was raining and less than 5C. 

Last one to leave the shade of the trees in the evening on hot days.

Tachypnea: Slightly faster breathing with no obvious cause. 

A raspy type of breathing.

Changed shedding pattern. The belly and chin may be the last to shed. 

Horse may be later and later shedding each year.

Odd cat hairs. (Those long wiry hairs) Often down the back of the cannon, sometimes elbows, and there may be only half a dozen, and they haven’t shed. The sort of thing you just snip off and think nothing of it. 

Coat colour: colour changes, lighter colour and often slightly more “gingery” than expected. Diet changes may help so you may think that you got it sorted.

Uveitis: - recurrent Infections slow to heal: Eg a virus/cold lasts a week when the other horses were fine after 3 or 4 days. 

The same with minor cuts being slow to heal, or the horse suddenly becoming prone to rain scald or a magnet for lice. 

 Increased incidence of infections: e.g. repeated respiratory infections, hoof/sole abscesses, tooth root infections or sinusitis

Insect bites: Severe reactions and swelling to fly bites. Sometimes golf ball sized swelling that oozes. 

Itching and other skin issues: Itching thought to be feather mites but hard to get under control. 

Pinworm, and other unresolved skin issues.

Niggling Tendon issues or odd tripping: ie horse would knuckle over on the hinds occasionally.

Lethargy: The ride that used to take 15 minutes, now takes 30 minutes. 

Pinning ears back when asked for more. 

 Horse only happy to trot when others cantering.

Muscle and Topline: Looks a little under-done or a tiny bit of a hay belly when in full work. 

You may wonder about weight loss or find you need to increase feeds above what was normal a year ago. Diet may improve this for a while but then they keep needing more. 

Easy keepers becoming hard keepers.

Subtle hoof issues: such as stretched white line even with good trim, short-striding on harder ground even if it corrects after a few strides. 

Spontaneous lactation in mares without foals.

Swollen sheath or udders for no apparent reason.

General blood tests may show increased liver enzymes, neutrophilia, lymphopenia, and anaemia. More of a high end of normal than definitive issues.

Fecal Egg Count suddenly above the norm for that horse.

Mood changes - Sensible horse gradually becoming spooky and more easily stressed.

Laminitis – ongoing and unresolved laminitis events are a huge red flag

Crests, fatty deposits: – present in horses that are generally easy keepers, that fail to lose the crests and deposits even with careful management and weight loss. 

Bulging eyes: - Bulging eyes (the hollow above the eye) that are a result of redistribution of supraorbital fat. 

IMPORTANCE OF DIETARY SUGAR + STARCH LEVELS

Horses diagnosed with PPID and more so if IR also (PPID and IR can go hand and hand), a diet low in sugar and starches is an absolute must. Starch must not exceed 4% and combined Starch & ESC% should aim to be no more than 10%. 

 Be aware as not all feeds stating they are low starch are actually 4% low in starch! Read your feed bags! 

If it is not stated what the starch and ESC% is, ring the feed company and enquire. 

This type of diet is actually a good base for all horses, especially pleasure horses, easy keepers, weekend warriors etc!

IMPORTANCE OF RECUDING IRON IN THE DIET

Metabolic horses including PPID respond well to removing added Iron in the diet and aiming to balance the Iron, Copper, Zinc and Manganese ratios to 4:1:3:3.  You can find out more about this important ratio and how you can reduce Iron in the diet here.  Remember to not get too caught up in it as Iron is the most abundant heavy metal on the planet and is present in pretty much all feeds.  Look out for copra (if feeding keep to 1/2 cup), Beet (if feeding make sure you are rinsing until beet water runs clear), most commercial feeds have Iron (Ferrous) added - check labels, some in very high levels and be carefully of the health product - Zeolite, it is 99% Iron. 

MORE RESOURCES

For reliable sound research based information relating to PPID or if you are starting a PPID journey with your horse and especially the start of Prascend medication, Equine PPID (Cushings) | Facebook page is an excellent start. It has a huge amount of information on what to look for, what to test, how to test, how to administer Pergolide, avoid the common Veil.

Alternatively the www.ecirhorse.org website is a wealth of information.  You will note HHIO recommended diet aligns with this. 

Recommend if in doubt or unresolved issues to get your Vet to test your horse especially if equine is prone to laminitis, has fatty deposits/crests and wont loose weight easily or unresolved ongoing infections. If your particular vet doesn’t test for PPID or doesn’t think your horse has elevated ACTH levels, find a vet that will!