Mention laminitis to most people and they automatically think that you’re talking about fat ponies eating too much grass.
The condition, however, can rear its ugly head in other areas of the equine population as a result of problems after foaling, use of corticosteroids, inappropriate diet or concussion. The latter is likely to be a cause in susceptible animals as the heatwave bakes the ground.
“Susceptible animals” are not only ponies in active service during the school holidays, but also show horses and racing thoroughbreds. These groups may be even more susceptible because they might be competing on hard ground and eating the kind of diet that makes them more prone to the condition.
The fundamentals are the same, but while ponies suffer mainly from massive sugar overload caused by rich grass, the problem in race and show horses is often caused by diet.
When a high-starch, low-fibre diet is given, the starch can override the digestive capacity of the small intestine and end up in the hindgut. Starch in the hindgut is abnormal and disrupts its normal function, leading to increased acid being present.
This is especially true if small amounts of forage are given, and likewise if large quantities of maize are fed. Maize is the slowest of the cereals to be digested and many high-energy mixes are high in maize.
A low-fibre diet has a double effect; food passes through the small intestine more quickly and it reduces the physical movement of the hindgut. This chain of events — less gut movement and an increase in hindgut acid — can lead to inflammation of the laminae. The theory about how this actually happens is not yet clear and is currently being researched.