22/03/2026
๐ฅ ๐๐๐ฐ๐ฒ๐ฟ๐ป๐ฒ, ๐๐๐ฝ๐ถ๐ป๐, ๐๐ผ๐ฝ๐ฟ๐ฎ ๐ ๐ฒ๐ฎ๐น โ ๐๐ผ๐ ๐ผ๐ฟ ๐ก๐ผ๐?
๐ด Iโve made special mention of lucerne, lupins and copra meal in this article because they are some of my favourite ingredients to recommend when formulating diets for horses, and when they are tarred with the โhotโ brush, I take notice.
๐ To begin, what is the definition of a heating feed? The answer likely varies from person to person, because everyoneโs perception of what makes a feed โheatingโ is understandably different.
๐ฝ For me, a heating feed is one that provides energy in a quick-release form, which typically goes hand in hand with being high in non-structural carbohydrates (sugar and starch). In short, these feeds can cause rapid spikes in blood glucose which = a sudden spike in energy.
โ๏ธ By my definition, lucerne, lupins, or copra meal are not heating feeds because they are all low in non-structural carbohydrates, meaning their energy is released slowly.
โ I believe the negativity surrounding these feeds mostly stems from the fact that they are a great source of digestible energy (calories) provided as fibre, protein, and fat. They can be unfairly blamed for changes in behaviour or energy levels for several reasons unrelated to the actual ingredient itself:
โ Too much energy is input relative to the energy output.
๐ Sometimes these ingredients are introduced to improve body condition; however, what is often overlooked is the horseโs actual digestible energy requirement relative to its age, body weight and workload.
๐๐ผโโ๏ธ It is incredibly easy to overestimate a horseโs workload intensity โ a pattern I see repeatedly during nutritional consultations. Owners often describe their horse as having a moderate or heavy workload, but when broken down into frequency, duration and intensity, the workload is typically light and not particularly demanding. *This is likely a topic worth exploring further in a future article to help owners better assess where their horse truly sits on the workload intensity scale โ let me know if this is worthwhile expanding on.
โ๐ผ *Any* ingredient has the potential to undesirably increase energy levels if enough of it is fed, regardless of its nutritional makeup and energy form. In this kind of instance, the excessive energy levels have nothing to do with the ingredient in itself, but rather with the fact that the horse is taking in too much energy relative to how much it is expending. Additionally, if a horse is being reconditioned after being in suboptimal body condition or suffering from a lack of food/calories, it is very possible that it simply feels better and can display its personality more willingly.
โ Dietary changes implemented too quickly.
๐๐ป Horses have a highly sensitive gut microbiome, and microbial populations can be easily disrupted by sudden feed changes. Introducing new ingredients without gradual introduction increases the risk of undesirable microbial population shifts, which can contribute to hindgut acidosis and general digestive disturbances. The result? A horse that may appear reactive, sensitive or irritable โ not because the feed is โheating,โ but because the gut is unsettled.
โ Secondary deficiencies and imbalances caused by dietary changes.
โ๏ธ At times, feeds are added to a diet without considering how the diet as a whole may be influenced. Feeding too much of one nutrient can sometimes induce a secondary deficiency. An example of this is feeding too much copra meal (a great source of phosphorus) without ensuring adequate calcium is provided elsewhere in the diet. The result of an inverted Ca:P ratio can be calcium resoprtion from bone stores. Another example of a secondary deficiency is feeding too much lucerne (often high in potassium) without providing an appropriate amount of sodium (salt). This could trigger an electrolyte imbalance that directly influences muscle function, nerve signalling, and you guessed it, behaviour.
โ Environmental, lifestyle, or management changes.
๐ง๏ธ Oftentimes, changes in diet coincide with other changes in the horse's life such as a weather event, travel to a competition, a paddock change, or a shift in herd dynamic. Something as simple as a good shower of rain that triggers grass growth could cause gut microbiome disturbances (see the point above regarding implementing dietary changes too quickly) that can then influence behaviour and energy levels.
โ Ingredient sensitivities, allergies, or intolerances.
๐ฑ Ingredient sensitivities, allergies, or intolerances are rarer than many choose to believe, but people often blame them first when implementing feeding changes because navigating the other points is too difficult. Don't get me wrong, sensitivities, allergies, or intolerances are absolutely possible and I am aware of several horses who undoubtedly cannot tolerate certain feed groups or ingredients; however, these horses are the exception and do not create a blanket rule for labelling any ingredient as "heating."
๐ฅฅ Lucerne, lupins, and copra meal are some of my favourite ingredients for horses when fed as part of a balanced diet. Any calorie sourceโwhether oil, beet pulp, or cracked cornโhas the potential to cause behavioural and energy changes (sometimes for better, sometimes for worse). Sadly, misinformation can be spread based on isolated experiences that fail to consider all contributing factors.
๐ฅ So if youโve made it this far โ no, lucerne, lupins and copra meal are not โhotโโฆ but an unbalanced diet will be, every time.
