Written by Sharon Smith MSc SEBC(Reg) IEng BHSAPC
This article follows on from part 1 where Sharon discussed the common causes and best prevention techniques for laminitis. In this, Part 2 she will discuss how laminitis is commonly treated and how to manage the laminitic horse.
In the previous article (read part 1) we established that:
- Laminitis is a progressive condition, with time being of the essence for severity and chances of recovery
- The key to avoiding detachment of the pedal bone (‘founder’ and ‘sinker’) is maintaining the health of the basement membrane, ie. the ‘glue’ holding the soft laminae to the lamella plates. Dead cells don’t stick
- High insulin and chronic inflammation challenge the laminae/lamellae bond, in a number of ways
- Many risks are avoidable through appropriate diet, exercise, low-stress lifestyle and controlling PPID
In this article I’m going to address some of the treatment strategies, mechanisms at work in the feet, and the recovery period.
Inflammation and ice therapy
If our finger is damaged in an accident, the advice would be to put it straight into ice and take some painkillers and anti-inflammatories, if we can. In ice, the arteries in the hand close up and shunts are activated, diverting incoming blood away from the finger. We exploit a reflex that evolved to conserve core body temperature. Swelling and bruising is reduced. Platelets in the blood have time to plug the gaps in the torn blood vessels, when the pressure stabilises. The reduced volume of swelling means there is less damage to clear up, and recovery time should be shorter. Ice also acts on the nerves to reduce pain before the painkillers start to work.
Ice is used in the same way to control blood flow to the horse’s foot at appropriate stages before, and during, acute laminitis. Before laminitis?! Consider the discovery of an obese, retired horse gorging on a bag of oats intended for a racehorse. High insulin levels combined with high blood sugar are extremely likely to trigger acute laminitis. It would be a good idea to divert blood from the laminae and basement membrane by placing hooves in ice. Any remaining blood flow to the foot will be helpful in maintaining the tissues. This strategy has been tested under prolonged (48h) controlled conditions and proven effective with the right equipment [1,2]. When the vet arrives, they may then prescribe pain-killing/anti-inflammatory medication. Hoof ice therapy is also used as a precaution with mares with retained placenta (likely to experience toxic challenge from decay of tissues) and horses with a virus fever or other-wise experiencing an infection; like sepsis and colitis [1,3].
Other foot-sore horses (ie. vibration/concussion damage) might find some pain relief in short bouts (20min) of ice therapy, initially. Yet, ice could be counter-productive where the blood flow is already severely restricted. Almost stopping the blood flow causes damage. Standing for prolonged periods on cold ground may also cause problems , especially for horses with a compromised ability to thermo-regulate eg. those with PPID. The blood flow may be insufficient to maintain the laminae, resulting in dead tissue. Warm leg wraps, that reach the coronet band, have been observed to help (author’s observation). Comfortable, warm footing encourages normal blood flow for the repair of damaged tissues.
A vet will advise whether sustained periods of ice therapy are appropriate to an individual according the stage of laminitis and other underlying health conditions.
Mechanical stress and foot support
Mechanical stress on the hoof wall contributes significantly to laminae separation. The toe area is most vulnerable if walking. While standing, the frog may help spread the load from the hoof wall. The horse should not be forced to walk.
Neither the hoof wall nor the digital cushion/frog would naturally take the full weight of the limb for prolonged periods. Considerations for damage limitation include: individual hoof conformation; footing; environment and degree of rotation of the pedal bone. The decision to remove or retain shoes is based on whether pressure and pain would be relieved by spreading the load using the frog and sole. Shoes are normally removed. A deep soft bed and cushioned flooring also helps to lessen vibration through the foot. Then, shifting own weight or a short step or two to drink and eat, should be sufficient to keep circulation around the foot. Slings and mechanical supports can help horses reliant on one foot for support, because the opposite limb is non-weight-bearing .
Prolonged stabling can also challenge the respiratory tract. Maintain good ventilation and a low dust environment, including steaming hay. A quiet companion may help stressed horses cope, even if the area has to be made slightly larger to accommodate the extra horse. It isn’t necessary to knock down walls; perhaps create a small area outside the stable door, effectively doubling the floor area. Stressed, unsettled horses are at risk of damaging themselves further. A turnout pen (5m x 5m) next to other horses, substituted for box rest for my own horse under different circumstances, with vet permission. This allowed a little extra room than a stable to avoid entanglement with the fence. We were lucky with the weather, as shelter was not always accessible. However, pasture consumption should be avoided during recovery from laminitis  and so fences must be secure and high, and still may be too great a risk to take with some determined or agitated horses. Prescribed sedatives may be necessary. The decision to subject a horse to many months of restricted movement should be considered carefully on welfare grounds and chances of recovery. Horses do not have human ambitions and cannot understand that one day they will feel better.
The recovery period can be used to investigate the reasons for the laminitis and put in place measures to address any controllable risks. Obesity must start to be addressed immediately, regardless of the severity of the laminitis episode. Recovery from an episode will be 9 – 12 months, so there is time to achieve this without abrupt starvation tactics. Latest advice is to not feed less than 1.5% bodyweight per day (measured as dry matter). Ensure any feed has a Non-Structural Carbohydrate (NSC = starch + sugar) level less than 12% – even if approved by laminitis organisations. Arrange to have forage analysed repeatedly, as it could contain more than 12% NSC – no matter what stage of growth or time of cut. Straw should also be analysed  and use a slow-feeding device that has evidence that it slows the horse down, like the Haygain Forager. Supplement a forage-based diet with vitamins (esp. Vitamin E at 150 IU/kgDM in diet) and deficient minerals and ensure essential amino acids are suppled through quality protein sources. Complete feeds may make matters easier.
Balancers are the only concentrate that could be fed ie. fed at less than 100g product per 100kg bodyweight . The horse does not need extra calories, even if they were fit competition horses before the laminitis. If in any doubt, consult an independent registered nutritionist, who can advise on the full variety of products available on the market to suit your horse’s individual needs.
Adhere strictly to the vet’s advice! The damage lasts longer than the pain. The prescribed ‘dose’ of exercise should be treated with the same respect as a dose of medication. Use a stopwatch and allow for walking to and from the stable within the prescribed time. It is likely to start with a few minutes of in-hand walk, on a soft surface, in a straight line. The horse may have other ideas about walking or returning to the stable when faced with potential freedom. Wear a hard-hat, gloves, protective footwear, and use a bridle with the reins split as a precaution. Mild sedation from the vet can be used until the feet can withstand a little jumping around, if necessary. Physical damage is a bigger welfare and safety risk than use of medication and mild sedation.
In summary, laminitis is a complex condition with multiple risk factors and degrees of severity. There are lots of good resources available online, but one may seem to contradict the other at first glance. When this arises, consider what might be challenging the adhesion of the laminae to the lamella, and whether the information is only applicable for a specific severity and stage of development of the laminitis condition. I always question invasive treatments or management and consult my vet and farrier about my own horse before acting. But one universal truth in biology is: dead cells don’t stick!
 Kullmann, A., Holcombe, S. J., Hurcombe, S. D., Roessner, H. A., Hauptman, J. G., Geor, R. J., & Belknap, J. (2014). Prophylactic digital cryotherapy is associated with decreased incidence of laminitis in horses diagnosed with colitis. Equine veterinary journal, 46(5), 554-559.
 Grenager, N. S., & Orsini, J. A. (2012). What's new in laminitis research? II: advances in laminitis treatment. Journal of Equine Veterinary Science, 32(10), 647-653.
 Eps, A. W., & Pollitt, C. C. (2009). Equine laminitis model: cryotherapy reduces the severity of lesions evaluated seven days after induction with oligofructose. Equine veterinary journal, 41(8), 741-746.
 Kellon, E.M. (2015). Winter Laminitis [online] ECIR Group Inc. Available from: https://www.ecirhorse.org/proceedings-2015.php [Date accessed: 25 Feb 2018]
 Geor, R.J. & Harris, P. (2013) Section E Clinical Nutrition: Laminitis In Geor, R. J., Coenen, M., & Harris, P. Equine Applied and Clinical Nutrition E-Book: Health, Welfare and Performance. Elsevier Health Sciences (27), 469-486.
 Watts, K. A. (2004). Forage and pasture management for laminitic horses. Clinical techniques in equine practice, 3(1), 88-95.