Fuelling The Show Jumper: What The Feed Bucket Decides
How Energy Source Shapes Composure, Stamina And Soundness
Halfway round a Grand Prix track, with fences rising to 1.60 metres and the Gulf sun pressing down on the sand, a show jumper is already burning through nearly half of its entire energy reserve simply lifting itself off the ground. Multiply that effort across 10 to 16 obstacles, several of them combinations, and the scale of what a competition horse demands from its daily ration becomes difficult to ignore. Many top-level routes then call for a second round on the same card, doubling the bill long before recovery can even begin. Get that ratio wrong, and the cost is rarely just a condition. It can be composure, rhythm, and, in the unforgiving arithmetic of a jump off, the difference between a clear round and a costly mistake.
Few people have spent longer translating that arithmetic into feed buckets than Dr John Kohnke, BVSc RDA, a veterinarian whose consultancy work has carried him through major show jumping stables. His verdict, distilled for decades at the coalface of equine nutrition, is that the fuel poured into a horse shapes far more than its waistline. It shapes temperament, stamina and, increasingly in a region where track-side temperatures soar through summer, the ability to simply stay cool enough to perform.
Fat And Fibre: The Foundation That Outperforms Grain
Every feeding plan, in the veterinarian's view, begins with roughage. Good-quality hay, long-chopped chaff and pasture turnout, where available, should anchor between 50 and 60 percent of a horse's daily dry feed intake by weight. Get that proportion right, and the hindgut rewards the horse with what the veterinarian calls "the best and most natural 'cool' energy source for horses", the Volatile Fatty Acids produced as fibre ferments. A 500-kilogram elite show jumper consuming around six kilograms of a blend of alfalfa and grass hay each day can draw roughly 50 Megajoules of Digestible Energy from roughage alone, supplying both quality protein and the fermentable fibre that keeps digestion settled.
That foundation, however, cannot alone cover the 110 to 120 Megajoules a top-level jumper needs daily to hold a lean frame and recover from the impact of a round, let alone a second round on the same card. The shortfall is best filled, in the consultant's recommendation, not with mountains of grain, but with oil. Vegetable oils such as canola, sunflower, soybean and rice bran deliver roughly 37 Megajoules of Digestible Energy per kilogram, nearly three times the density of cereal grains, while behaving in the body as a "cool" or slow-release source. "Unlike large amounts of grain starch, they provide sustained energy without contributing to the excitable behaviour that can compromise composure and precision in the show-jumping arena," Kohnke explains, a distinction behind why many of the stables he advises now build oil into the ration gradually, increasing intake by around 50 millilitres every five days so the small intestine has time to adapt.
Many busy yards, managing large numbers of horses, lean instead on processed commercial feeds for convenience, extruded, micronised, or steam-pelleted mixes that typically supply 12.3 to 13.5 Megajoules of Digestible Energy per feed and are often boosted with 5 to 7.5 per cent fat as vegetable oil. The trade-off, the consultant cautions, is that oil in some cooked feeds is prone to oxidation and rancidity once a bag is opened, a process that also damages fat-soluble vitamins. Specialised supplementation of Vitamins A, D, E and K, he notes, should be added to any high-energy ration to protect muscle and nerve function.
Why Starch Excess Undermines Composure And Soundness
Grain still has its place, supplying Non-Structural Carbohydrates that fibre and oil cannot provide alone. But the veteran nutritionist is blunt about the cost of overreaching starch. Push too much through the small intestine, and the surplus spills into the hindgut, where acid-producing microbes ferment it rapidly, generating D-lactic acid and tipping the gut towards acidosis. The consequences run well beyond digestive discomfort. "Hindgut acidosis may lead to nervous behaviour, loose or sour-smelling manure as well as low-grade laminitis," he warns. Horses affected, the consultant adds, often develop "sore feet, reduced stride length, reluctance to jump or may stumble on landing", precisely the faults a rider cannot afford between the wings of a fence.
Not every grain carries equal risk. Raw oats, with a simpler starch structure, allow around 75 per cent of their starch to be digested efficiently in the small intestine, where barley and corn leave a far greater share, as little as 21 to 30 digested there, to ferment in the hindgut instead. Add soluble sugars from molasses or honey, and gastric acidity climbs further still. Feeding more than two grams of fermentable sugar or starch per kilogram of body weight in a single meal, the specialist warns, raises the risk markedly, a particular hazard for jumpers given how landing forces can drive acid up onto the stomach's sensitive lining. Left unmanaged, this can progress to gastric ulcers, leaving a horse facing "discomfort, poor appetite, girthiness, difficult behaviour and, in severe cases, refusal to jump".
It is a reminder, too, that horses are simply wired differently. Some, Kohnke notes, "naturally have more sensitivity to grain starch, which may lead to increased excitability and over-reactive behaviour", which is why the nutritionist prefers to divide moderate grain rations into multiple smaller feeds rather than loading one or two large ones. The aim, as he puts it, is a horse that stays "responsive, focused and easy to ride", not one running hot on its own feed.
Electrolytes: What The Heat Takes And Why It Matters
The show jumper's sweat is not just water. Each litre lost carries sodium, chloride, potassium, calcium and magnesium — minerals governing muscle contraction, nerve signalling and fluid balance — and the losses accumulate at a rate a standard electrolyte schedule built for temperate competition cannot match. Kohnke is direct in the response: "Under hot conditions, trainers need to increase the daily electrolyte supplement," with the mix weighted deliberately towards calcium and potassium salts, "as they are lost in greater proportions in heavily or free sweating horses." Compounding the sweat equation is the diet's own thermal contribution.
Protein fermenting in the hindgut generates what Kohnke identifies as up to six times more internal heat than the breakdown of carbohydrate or structural fibre — an effect he flags as especially consequential "under GCC climatic conditions", where that internal load compounds whatever the horse is already shedding through exertion and ambient temperature. Overfeeding alfalfa and chaff, excellent protein sources in moderation, can in this context work against a horse in summer training as readily as they help it through winter.
Top trainers globally are increasingly looking beyond the feed bucket to supplementation, but the principle Kohnke consistently returns to is that the foundation must be sound first. Fat-soluble vitamins A, D, E and K, he notes, "should be added to any high-energy ration to protect muscle and nerve function” particularly relevant where oil in opened commercial feed bags is already prone to oxidation and rancidity that quietly degrades their content. Beyond vitamins, trace minerals lost through sweat and the additional antioxidant demands of heat-stressed muscle tissue all factor into a supplementation programme built, in Kohnke's framework, on what the horse's body is measurably losing — not on what the label promises to add.
One Formula Never Fits All Horses
None of this, the BVSc-qualified vet is careful to stress, reduces to a single formula. "My experience over many years of consulting with major show jumping stables leads me to recommend providing a horse with a variety of energy sources each day," he says, pairing the slow release of roughage with the moderate release of oil and the rapid release of grain so a horse has access to sustained stamina and sharper bursts of power without tipping into excess heat or fizz. Horses receiving oil supplementation consistently through training, in the consultant's observation, "are often better able to maintain condition and conserve muscle glycogen during exercise", while moderate, multiple grain meals provide the responsiveness a rider needs without the fizz that comes from a single large feed.
On lighter training days, the consultant advises trimming the grain portion back to reflect that total energy expenditure falls to just 60 to 70 percent of a full competition day, replacing the difference with extra hay rather than simply leaving a gap. He is equally insistent on the value of regularly assessing body condition, muscle development and recovery after training, since, in the vet's words, "a horse should be maintained in a lean, athletic frame rather than carrying excess body weight". Excess condition, the specialist warns, "not only increases the energy required for take-off and landing but may also increase stress on bones, joints and tendons during jumping".
Individual variation, in his telling, matters as much as the formula itself. Some horses gain condition easily and need careful portion control to stay lean. Others run hot on starch regardless of how carefully it is managed, and need the balance shifted further towards fibre and oil. What does not vary, Kohnke maintains, is the underlying principle that feed is performance equipment, every bit as much as fitness work or schooling. Long after the gates close on an evening class in the Gulf heat, the horses travelling best through a demanding course, staying sharp at the in-gate and settled between the wings, are very often the ones whose feed room got the unglamorous arithmetic of hay, oil, grain and electrolytes right days before anyone climbed into the irons.