General Nutrition - Counting the Calories


Losing weight is tough but even tougher for the horse, who has evolved to spend most of his time eating so how can we help reduce an equine waistline whilst providing a balanced diet?


Fibre, fibre, fibre!

As the main source of calories for good-doers, forage intake may need limiting to encourage weight loss but not at the expense of gut health. An absolute minimum of the equivalent of 1% of bodyweight, in forage, is required to maintain gut function which equates to 5kgs per day for a 500kg horse. Strict strip grazing and the use of muzzles will help control grass intake but, when a paddock is really bare, be prepared to supplement with hay or haylage to maintain minimum fibre levels.

Divide this forage ration into as many small “feeds” as possible so that it is not all eaten in one go. Using small-holed hay nets and putting one net inside another will help make forage harder to eat and ensure that a small amount lasts a bit longer.

Coarse forage, with more stem and less leaf, is naturally less nutritious and less digestible so is preferable for good-doers. If your forage is soft and leafy, it’s likely to be more digestible and provide more calories but soaking it for at least an hour will help remove some of the sugar content and so reduce calorie levels. Other nutrients will also be removed by this, however, so some form of supplementary feed is essential to counteract these shortfalls.

What Else Can I Feed?

Modern pasture and forages are known to be lacking in a range of nutrients and when intake is controlled the nutrient shortfall for the horse is compounded.
Low calorie balancers are the perfect solution as they contain concentrated levels of quality protein, vitamins and minerals and are fed in very small quantities (typically 100g per 100kgs bodyweight). This helps to keep calorie intake down whilst ensuring horses receive a balanced diet with all the nutrients they need for health and well-being.

Chaff-based feed with added vitamins and minerals are designed to be fed in much larger volumes, thereby providing the horse with additional chewing time, yet they are often under-fed, with the horse missing out on nutrients as a result. Total feed intake (forage chaff/balancer) should equate to no more than 1.5% of the horse’s bodyweight so forage intake may need reducing if larger quantities of chaff are fed.

As well as looking at total diet as a percentage of bodyweight, we can look at the calorie intake ie. Digestible Energy in MJ/kg required per day. In order to encourage weight loss, we should feed 10% less than is theoretically needed for maintenance. For example, the total diet for an average horse at maintenance might provide 8 MJ/kg so a ration for one needing to lose weight needs to only provide 7.2 MJ/kg, forcing the horse to burn body stores of calories to make up the deficit and therefore lose weight!

Hay and low calorie chaffs can average 7 – 8 MJ/kg so in order to reduce overall calorie intake you may need to turn to oat straw as a partial forage replacement and feed a balancer instead of the recommended quantity of “fortified chaff”, in order to bring the total Digestible Energy level down.

Gradual Weight Loss

Horses who need to lose weight must burn more calories than they eat and a target reduction of 1% of bodyweight per week, or 25 – 30 kg of bodyweight over 4 to 6 weeks, is ideal. Exercise will be instrumental in helping to burn these calories, whilst the provision of a balanced diet should also help the horse feel more like working too.

Regular weighing or weightaping will be useful, with results plotted on a graph helping to give a visual representation of progress and also helping with diet calculations since the forage/feed quantities will need reducing as the bodyweight decreases.

No equine should ever be starved as this can cause digestive upsets, or worse, so, like all changes to the diet, where a drastic reduction in food intake is necessary, it should not be too abrupt. Hyperlipaemia is a condition that arises when the body is starved of energy and excessive fat is mobilised to compensate. As a result, free fatty acids and triglycerides are released into the blood stream and, in excess, can cause liver and kidney failure. Prolonged periods without food are, therefore, not only risky but will also increase the likelihood that the horse eats more voraciously when access to feed is resumed.