Footy:

Footy was investigated for EPGH at his owners request because he seemed to urinate a lot and she felt he had a slightly abnormal coat for a show horse in summer. He had blood collected at the clinic, and I warned that this would affect the results because he had a float trip and there is the usual excitement. Due to the inconclusive result (pathologist’s comments follow) he was retested at 9.00 am after a normal night at home, before he was hungry or any horses were moved about. The results indicated no abnormality.

Pathologist’s comments: “Resting normal insulin (5 – 36 micro U/ml should be interpreted with great care. Many horses with Cushings disease are indeed found to have elevated resting insulin concentrations due to cortisol induced antagonism of insulin and also the pro-secretory effect of CLIP (one of the pituitary derived products in ECD cases). However, diet and stress also have profound effects on insulin secretion and these should be carefully considered. A hard feed will elevate insulin levels for up to 5 hours. Insulin levels as high as 250 uU/ml may also be seen in non Cushings horses with painful conditions such as colic, and it is likely the pain of laminitis could have a similar effect. Thus insulin is not a suitable test for ECD horses with active laminar pain, and also is best measured first thing in the morning before feeding”.

This horse had no signs of laminitis and testing in the morning at the property delivered a normal result.

Name Age Diagnosis Re-Test Current Status
Horse Gelding Footy 14 5th/12th/2005
insulin 55 uU/ml
glucose 6.4 mmol/L
insulin/glucose ratio 64.6 ( < 30)
All Normal I have not heard how Footy is going. I am assuming he is still normal.

Trojan:

After several years with severe lameness secondary to laminitis and Cushings symptoms including an extremely long, shaggy coat in winter, Trojan was diagnosed in March 2005.

After 6 weeks of treatment, a blood test revealed a further 1 mU/L increase in insulin and the dose of Pergolide was increased. Trojan improved noticeably within days. However, he eventually succumbed to severe lameness in one foot despite expensive hoof reconstruction and therapeutic shoeing, which had initially resulted in great improvement.

Mid-way through the treatment period, Trojan was off all pain relief and cantered for the first time in years. When wet weather set in he had significant lameness in his most affected front foot which did not respond to therapy, and after 10 days of treatment and high doses of phenylbutazone, the owners chose to euthanase him to end his suffering.

Name Age Diagnosis Re-Test Current Status
Horse Gelding T 23 10/3/2005
insulin 17 mU/L
glucose 4.4 mmol/L
17/3/2005
18 mU/L
5.0 mmol/L
After increasing medication and an excellent response T was euthanased due to severe lameness in one foot secondary to chronic laminitis.

Jess:

A much loved and still ridden Appaloosa mare, with severe chronic laminitic changes to the feet and only mild observable changes to the hair coat and skin. Lameness prompted the owner to contact me, and after much discussion a blood test indicated the mare was strongly positive for EPGH.

Treatment with Pergolide was combined with Vitex agnus cactus dried herb, and the mare was returning to soundness quickly. At the 6 week re-test, the insulin level had returned within the normal reference range (from 113 down to 22.2 in 6 weeks).

Treatment for the laminitic changes to the feet are continuing, and the mare is now ridden gently. Her overall health and coat have improved.

Name Age Diagnosis Re-Test Current Status – deceased.
Horse Mare Jess 22 8/3/2005
Insulin 113 mU/L
glucose 5.5 mmol/L
4/5/2005
20.2 mU/L
6.0 mmol/L
2005 – Excellent response to treatment. Decrease medication & herb. 2007 – Has had a few relapses and went off treatment. Back on now and going well. Since this time 4 years of treatment and improved helath and soundness the mare was taken off treatment and several months later developed severe laminitis and was euthansed. This has happened many times where people think that the horse or pony is better and stop treatment. The result is relapsing into worse condition than before they had treatment.

Pony M:

This older pony-cross mare is improving in health after her owner visited the vet clinic describing her horse as pot bellied and exercise intolerant. The symptoms were suggestive of EPGH, despite the owner saying the hair coat was normal and the horse appeared well.

Blood tests revealed a high level of insulin, and treatment with Pergolide commenced. Research into the use of Vitex agnus cactus prompted the inclusion of this herb in the daily treatment program, and at the 6 week re-check of insulin levels, a significant improvement was noted. Therefore, the dose of Pergolide was halved and theVitex agnus cactus continued at the same dose.

The goal is to recheck at 6 weeks and if necessary further reduce or eliminate the Pergolide while continuing with herbal therapy.

Name Age Diagnosis Re-Test Current Status
Pony Mare M 20 20/4/2005
insulin 30 mU/L
glucose 4.7 mU/L
9/6/’05
4.7 mU/L
4.3 mol/L
Good response to treatment. I saw this client 18 months later and mare was getting worse. Advised re-test and increase dose of pergolide. This case highlights the importance of regular monitoring.

Mare M:

After a long career in a riding academy this mare was diagnosed in an advanced stage of the disease. The owner of this mare was intending to contribute to this topic by treating the mare with Vitex agnus cactus only, rather than combine it with Pergolide, or use Pergolide only. Before it was possible to commence treatment the mare contracted a respiratory infection and due to her advanced age and poor general health the owner made the difficult decision to end her suffering.

Name Age Diagnosis Re-Test Current Status
Pony Mare M 23 Insulin 167 uU/ml
glucose 5.9 mmol/L
amended ratio 219.2
cortisol 54 nmol/L
Euthanased due to respiratory infection and old age.

Jorge:

A longer than 2 year history of laminitis with long periods of being sound in between. Jorge was going well, but after a mild dose of laminitis followed by a severe foot trim he continued to get worse. Jorge was shod and was much improved, but then continued to decline again. Diet, environment and feet were well managed and pain relief did not bring about a change in the symptoms.

Blood testing revealed the laminitic metabolic profile and Jorge has been treated with pergolide to try and resolve the laminitis. He is also on a diet plan to lose 30 kg, to increase his exercise, and to get him out of his current insulin resistance. So far so good. March 2007 still sound and being exercised. On low dose pergolide & vitex agnus cactus.

Name Age Diagnosis Re-Test Current Status
Pony Gelding Jorge <10 Insulin 167 uU/ml
glucose 5.9 mmol/L
amended ratio 219.2
cortisol 54 nmol/L
Due in a few weeks. Laminitis improving. Has no classic EPGH but fits the metabolic profile for laminitis.

Summer C:

Has been slowly developing EPGH symptoms with laminitis. We are in drought conditions at the time of writing so the chance of carbohydrate overload in these cases is zero. The mare has front shoes, and was worsening despite pain relief. She is improving on pergolide. Plan – retest and adjust dose rate if needed.

Pathologists comments: “Cortisol – A single random cortisol result may be of limited diagnostic value due to the variable secretion of both ACTH and cortisol. Dynamic testing i.e. the overnight Dexamethasone suppression test, is recommended to assess for EPGH or Cushings-like disease. Please contact the lab if you require a protocol for this disease.” (Do you think that was a hint)? I don’t do dex tests in these cases as more corticosteroid is likely to be detrimental to the laminitis, and could tip the patient over the edge. I do a treatment trial instead.

March 2007. Did this mare’s feet myself which led to improvement, I blood tested normal. Re-shod November 2007, going very well. Increased dose of pergolide to 1mg daily, but mare did shed her winter coat and her laminitis is now controlled. March 2008 summer – was enthanased due to complications from a tooth root abscess, foot abscess, and a tight bandage. My condolences to her family, who tried very hard to save her. However, she is no longer suffering from her chronic laminitic feet.

Name Age Diagnosis Re-Test Current Status
Summer C 20+ insulin 91 uU/ml
glucose 4.9 mmol/L
cortisol 85 nmol/L
Nov Mal insulin 200/ml & sound again. Laminitis and other classic Cushings signs. Some improvement after 7 days and will retest at 6 weeks. Nov 07 very well.

Todi:

Todi had her last foal at 22 without complication. She survived 2 bouts of colic and 2 rattlesnake bites and enjoyed good health all her life, with only a few bouts of laminitis. To her owners distress, in the last few years she began to lose weight, with chronic laminitis, and abscesses associated with her teeth despite regular dentistry. The weight loss became severe and through www.farriervet.com I corresponded with Jean in the USA about this horse and advised that after tests by her local vet, which indicated Cushing’s disease, that Pergolide should help. Jean was naturally very anxious about using this drug as she has a holistic philosophy (as do I).

Jean reported a positive response to treatment and I know that seeing her horse respond well makes it easier for Jean to continue treating Todi. At the time I considered the treatment palliative, and for quality of life not quantity. However, I am happy to say that at the last e-mail, Todi was shedding her coat and doing well despite a very harsh winter. She was eating as much as she could and had regained some weight.

Name Age Diagnosis Re-Test Current Status
Horse Mare Todi 25 Tests performed
13th March ’06. Dex suppression test, ACTH, thyroid and insulin.
Retested July,
August & September 2006 ACTH & insulin.
Pergolide
1 mg/day.
Herbal treatments April, May, June ’06.
Euthanased by owner due to ongoing difficulty of treatment and the harsh winter conditions where this horse lived. 1/12/07.

E-Why:

Laminitic for greater than 5 months with diet, environment and feet well managed. Suspected metabolic cause of laminitis, and this is the first pony that I have tried pergolide on that did not present as classic Cushing’s disease. The results have been good, and this case prompted me to treat the other young ponies listed here with laminitis.

Pathologists comments 6/10/’06: “Insulin – the published reference ranges are in the region up 35 uU/ml so this indicates insulin resistance. Cortisol – In normal horses the range is above 55 nmol/L approximately, Dexamethasone suppression test recommended to investigate further”. Started a treatment trial instead. Result excellent, reduced medication after the first retest, and is now on minimal daily dose and has lost weight and increase exercise.

Name Age Diagnosis Re-Test Current Status
Mini Pony Gelding E-Why <10 6th/10th/2006
insulin 119 uU/ml
glucose – normal
cortisol 95 nmol/L
triglycerides 1.1
6th/12th/2006
insulin 6 uU/ml
cortisol 47 nmol/L
Much improved and on half the dose of pergolide.

Maybelle:

A much loved, very old and shaggy mini that had survived colic surgery once, was put down after developing colic again. She had chronic laminitis, however she improved with farriery and a diet change including supplements. It would have been interesting to see if pergolide would have helped her.

Name Age Diagnosis Re-Test Current Status
Mini Pony Mare Maybelle 30 10th/8th/2006
insulin > 300 uU/ml
Normal Euthanased before treatment given.

Tango:

A beautiful show pony with a 3 year intermittent history of laminitis. For the past 4 months he has been deteriorating. My fist meeting was in December ’06 and he was so severely laminitic that he could not bear to stand up. After an initial investigation into his laminitis I suspected a metabolic cause but he was deteriorating so fast in our summer weather that I was not sure we would save him. Breed and phenotype (how he looks) he is the classic candidate for laminitic metabolic syndrome.

I feel that hyperlipemia was part of his problem and that if his owners hadn’t given him 24 hour a day care, hosing his feet and loving him through he would not have survived this long.

Now at 4 weeks, he is out most of the day, going for walks and getting his spark back. He has a long way to go and I am reluctant to change anything too soon. I will re blood test him before touching his feet; we will also begin to reduce his medications including anti-ulcer meds and pain relief which is now at a very low dose. The owner is keeping a diary and I hope to present this case to other vets.

In early February 2007 Tango has been re-tested. At this time he was clinically dramatically improved, off all pain relief, standing comfortably, and moving comfortably, despite the dramatic crisis line below the coronary band that you would expect to see with such a severe case of laminitis. His blood results for cortisol, insulin and glucose were normal.

We have reduced the dose of pergolide to 750 micrograms per day, and the owner intends to also begin feeding Vitex Agnus Cactus with the plan to eventually get Tango off pergolide if possible. He will be on the laminits diet with antioxidants and other management changes for life. The family have set a goal to take him to a show in August this year, even if he is only an observer. Tango has a lot of living left to do. I strongly feel that if he hadn’t been treated with pergolide he would have been euthanased before Christmas ’06.

Name Age Diagnosis Re-Test Current Status
Welsh Pony X Gelding Tango 10 12th/12th/2006
insulin 224 uU/ml
glucose 9.2 mmol/L
cortisol 222 nmol/L
elevated liver enzymes indicating cholistasis
1st/Feb/2007
glucose 5.5mmol
cortisol 71nmol/L
insulin 8uU/ml
Significant improvement, has improved dramatically. Is off all medication except pergolide and is moving freely around the farm. 1/12/07.

I have recently tested a few more ponies, and the histories and results are similar to those above. When I have enough cases I hope to use this information as part of a small study into pergolide as a treatment for laminitis for those cases that have metabolic laminitic syndrome.

2008 – Tango and Jorge are both for the first time un-rugged, unfed, out in the paddock, doing it tough and both ponies are sound and healthy. They are loved, but it has taken a long time to convince the owners that less is more. When the weather turns really cold they will be supplemented. Tango is the best he has been for 18 months.