How to feed a ‘hotter’ horse is a dilemma faced by horse owners in many different disciplines. How do you provide a horse with enough dietary energy to do the work he needs to do at the level he needs to do it, while controlling the mental energy or reactivity? Here we examine this question, whilst cautioning from the outset that each horse is different and the best advice is always to speak to an equine nutritionist.
Behaviour and nutrition
It’s no secret that the relationship between behaviour and nutrition is not an exact science. Horses can be very individual in their reactivity to different diets. What works well for one horse might not work well for another horse. There are so many different feeding programmes, even among the top riders, and many reasons why there isn’t a one-size-fits-all diet: riders might have specific preferences or biases about feeds; regional variations exist in forage quality and availability; riders could want a specific feel from their horses; or the horses themselves might just respond differently to certain diets. The list is pretty endless!
The impact of diet
The diet component most often associated with horse behaviour is energy, or calories, which come primarily from dietary starches, sugars, fats, and fibres. Horses either immediately use calories supplied by the diet for energy in the form of circulating blood glucose, or store it for later use as glycogen in the liver and muscle or as fat in adipose tissue. When the diet provides excess calories and energy, most horses just gain weight while others become more reactive. The behaviour change noted is likely to be more pronounced when the dietary energy comes from starch and sugar rather than fats and fibres. Starches and sugars are classically felt to make a horse hotter, and fibres and fats are thought to provide the calories without the heating effect. That said, there are reactive horses and horses that are more laid-back regardless of the calorie sources, or even quantities. So, again, nutritional control of behaviour is an inexact science and takes some trial and error.
Note
The key to successfully feeding your horse is to remember that horses are anatomically designed to digest fibre (hay and/or grass). Therefore, a horse’s diet should maximise the amount of fibre. By maximising the amount of fibre in the diet, you can decrease the amount of simple carbohydrates (sugar) the horse needs to eat to maintain weight and condition. Horses require a minimum of 1.5% of their body weight in hay or pasture – for a 500 kg horse this equates to a minimum of 7.5 kg of forage.
General principles
However, transitioning from a grain-based, higher-soluble-carbohydrate feed to a fat and fibre-heavy, lower-soluble-carbohydrate feed formulated for performance horses is a good place to start if you are looking to reduce ‘hotness’. If a horse is an easier keeper, a low-calorie ration balancer is another option.
The best tool to help make sure you are not over- or underfeeding calories is to monitor body condition and aim to keep your horse at a 5 or 6 body condition score, adjusting the diet if needed to maintain a consistent and desired level of body fat stores.
A note on diet and lifestyle
The ‘natural’ diet for a horse is often very different to the performance diet we prove to a horse. The ‘natural’ diet allows the horse free-access to pasture. Given this opportunity, the horse will graze for approximately 16 – 18 hours per day, assisting a slow, continuous intake of fibrous feed into the digestive system. Further, the ‘natural’ diet has the added advantage of the horses being able to roam around the paddock providing the horse with an ample amount of natural exercise. On the other hand, the ‘performance’ diet typically consists of two or three meals per day to horses that are confined to a stable for many hours at a time. These horses often finish their meals – that commonly consist of high-energy grain and limited amounts of hay or chaff – quickly and then stand for long periods of time waiting for the next meal, with little to no natural exercise.
This stark difference between a horse’s ‘natural’ existence and his ‘performance’ existence is heavily to blame in creating horses with behavioural issues; therefore, outside of just changing the type of food, it is better to consider a holistic change to a more ‘natural’ lifestyle for the horse. Yes, he may still need concentrate feed and African Horse Sickness deters most of us from opting for 24/7 turnout, but more turnout, combined with constant access to hay is going to result in bigger behaviour improvements than simply reducing the sugar content of his diet.
Other considerations
It is also important to keep in mind there are many things besides diet that affect behaviour and mental attitude in horses. Discomfort, frustration, and fear can all contribute to what we describe as ‘hot’ tendencies in our equines.
Performance horses are especially at risk of gastric ulcers, and the discomfort these lesions cause can lead to over-reactivity. Similarly, kissing spines, navicular disease and arthritis can all cause horses to ‘act out’ due to pain.
For these reasons, it is important to have a veterinarian examine horses to determine if there are possibly medical issues or causes of pain or discomfort, especially when an individual horse demonstrates an unexpected change in behaviour, without a commensurate change in diet.
In the case of a horse experiencing gastric discomfort, for instance, he may benefit from both medical intervention and the implementation of nutritional strategies such as feeding small, frequent meals, including lucerne in the diet, and supplementing a product containing marine-derived calcium proven to support gastric health. The actual food brand chosen, however, is likely to have minimal impact.
Similarly, managing the pain the cases of kissing spine, navicular or arthritis may remove any need for dietary changes in horses afflicted with these conditions.
Final thoughts
When feeding horses to affect their behaviour, there is no one-size-fits-all approach. Before changing your horse’s feed, both look at your horse’s lifestyle and consult your vet to be sure your horse does not have physical reasons to be reactive under saddle or on the ground. If you are unsure about your horse’s diet, work with an equine nutritionist to determine how you can feed your horse to meet his needs without providing him excess energy.