Dr Jo Ireland from the Animal Health Trust, discusses how the national disease awareness initiative, Talk About Laminitis, has contributed to the advancement of veterinary understanding about the underlying causes of laminitis.

The Talk About Laminitis (TAL)

The Talk About Laminitis (TAL) initiative is aimed at raising awareness of the underlying hormonal causes of laminitis – PPID (Cushing’s disease) and equine metabolic syndrome (EMS). The initiative, supported by Redwings, The British Horse Society and World Horse Welfare, is now in its fifth year. As part of the scheme, the laboratory fees for the blood test which detects PPID (the basal ACTH test) are free.

 

Since its launch in September 2012, over 36,000 horses, ponies and donkeys have been tested for PPID through the scheme. The majority of these animals had clinical signs suspicious of PPID and overall over 50 per cent had positive test results, aiding the diagnosis of PPID in thousands of cases¹. This has contributed to PPID being recognized as the sixth most frequently encountered disease affecting horses in the UK. Previous research has identified age as the major risk factor for PPID, so it was not surprising that the TAL data showed the average age at diagnosis to be 20 years. While uncommon in horses less than 10 years of age, over a third of horses and ponies aged between 10 and 15 years that had clinical signs of PPID (including laminitis) were affected.

This has led to a revision of recommendations about the age of testing for PPID, with most veterinary surgeons now testing any laminitic case from the age of 10 upwards.

The warning signs

The TAL scheme also gathers details about clinical signs observed in horses being tested for PPID. The most common signs were:-

1. Current and/or previous episode(s) of laminitis (46 per cent of all animals tested);
2. Hair coat abnormalities or abnormal moulting/ hair coat shedding (32 per cent of animals tested);
3. Muscle wastage, particularly of the topline or hindquarter muscles (17 per cent of all animals tested).

Unsurprisingly, both the percentage of animals testing positive and the average ACTH concentration increased with increasing number of clinical signs observed. This suggests that early or mild cases of PPID may show very few obvious clinical signs, and that the presence of a number of clinical signs associated with PPID may indicate more advanced disease. Horses with active or previous laminitis were significantly younger than those without laminitis, indicating this may be the first clinical sign of PPID in many cases.

On the other hand, horses reported to have hair coat abnormalities or muscle wastage were significantly older than those without these signs, indicating that these signs may be recognised in more advanced cases.

The odds of a positive test result were increased for animals with a history of laminitis, and those exhibiting hair coat changes, muscle wastage or abnormal fat deposits above the eyes. This correlates with previous studies where the presence of coat changes or abnormal shedding showed the strongest association with PPID, and horses showing these changes had more than two times greater odds of being diagnosed with the condition.

References:

1. Boehringer Ingelheim, ACTH tests run via TAL 2012-2015; 2.National Equine Health Survey 2015

Scheme supporters

The Talk About Laminitis campaign is supported by a number of charities, including World Horse Welfare, the British Horse Society and Redwings. Here’s what they have to say about TAL and the risk of laminitis...

 

World Horse Welfare

“Laminitis is an extremely painful condition that can affect any horse, pony, donkey or their hybrids. While many owners are aware of the disease, there are still a lot of misconceptions that only certain types of horses are at risk, or it is more likely to occur in spring.”

“It’s imperative horse owners know all the facts about laminitis to help prevent it, be vigilant for the signs and take swift action as soon as any problem is identified.”

“PPID is a significant risk factor for developing laminitis and thanks to the TAL initiative, more cases can be identified early and provided with more treatment options and support for both horses and their owners. If they haven’t already done so, I’d urge horse owners to take advantage of the free PPID test and support offered by the scheme.”

British Horse Society

“Our BHS welfare officers respond to many welfare concerns where either acute or chronic laminitis is unfortunately already evident.”

"We always encourage horse owners to take advice from their vet without delay. It is vital PPID is detected early and a correct diagnosis is reached. We would encourage all owners of horses with PPID to make use of the valuable support being offered by TAL.”

Redwings

“Always call your vet immediately if you suspect laminitis – it is a veterinary emergency and incredibly painful for the horse.”

“Early intervention can prevent the development of permanent or catastrophic changes within the hoof and can often shorten recovery time and reduce the cost of treatment. There’s no such thing as a ‘touch of laminitis’ so never wait and see how the horse looks in the morning, just pick up the phone. As 90 per cent of cases are believed to be triggered by an underlying veterinary condition, it’s vital to test your horse or pony for diseases such as EMS or PPID. These conditions can often be easily managed with diet and/or medication and this will help prevent further attacks of laminitis.”

Case study

When Shirley Turner’s veteran suffered from a bout of laminitis, her vet advised a blood test to see if it had been caused by an underlying hormonal issue

“I had no idea that Arnie was at risk of laminitis””

Shirley Turner has owned 16 year-old, 14.3hh dark bay Welsh Cob Arnie, since he was three years old. She used to show him, but now he is older they mainly enjoy hacking out. Arnie had no signs whatsoever of laminitis until August 2014 when he suddenly went very lame in his left foreleg. Shirley called the vet out and initially they weren’t quite sure what was wrong.

Eventually, the vet confirmed that Arnie had laminitis and that it was present in all four hooves, although he was still mainly lame on his left fore. Once the laminitis had been diagnosed a blood test was taken to discover his ACTH levels. This came back as 89.5 which is high and confirmed that Arnie had PPID.

Making a difference

Arnie was prescribed medication (Pergolide) at half a tablet once daily. Five months later, when he was re-tested, his ACTH levels had dropped to 27.5, which Shirley’s vet was very happy with. Because of the diagnosis of PPID and laminitis, Shirley’s vet also advised her to restrict Arnie’s grazing and keep him in at night, to help him lose a little weight.

When Arnie started on the medication, he weighed 512kg, but by around six months later this had dropped down to a more healthy 448kg.

 

“I have has managed to maintain him at this weight ever since. I weigh him regularly, to keep a close eye on his condition.”

 

Arnie has his ACTH levels tested every six months, in order to monitor his PPID. Last August his levels had crept up, so his medication dose was adjusted. Shirley is now waiting for the result of his most recent ACTH test.

“Since Arnie was diagnosed with PPID, I have used the TAL Care and Connect online service, and found the information available on PPID and laminitis really useful.”

“You can set up a profile for your own horse on the site, and use it to record his test results and weight.”

“My vet recently came out to see Arnie and I was delighted when she told me that she thought Arnie looked really well and that she was pleased with him.”

“I was delighted when my vet came out recently and said Arnie looked well”