Equine Obesity

Obesity in horses and ponies is an ever-growing concern and affects many more equines than people believe. It is now thought that up to 70%[1] of the UK’s equine population is now overweight.

Becoming overweight is a physiological response to a positive energy balance, when energy consumed exceeds the energy required by the individual. This excess energy is laid down as adipose or fat tissue which can be distributed equally across the body, or concentrated in specific areas, such as the crest of the neck or across the tail-head. It’s important to remember that there will also be fat tissue laid down around muscles and organs within the body cavity which can lead to more severe health complications.

People are quick to judge a lean horse, but those who are carrying excess weight are just as unhealthy. Horses that are overweight are more at risk of Equine Metabolic Syndrome (EMS), laminitis, circulatory problems, reproductive issues and excessive loading of the limbs and joints.

Assessing bodyweight
As part of responsible ownership, it is important for owners to monitor their horse or pony’s bodyweight on a regular basis to adjust feeding and/or exercise regimes accordingly.

There are several ways in which weight can be monitored on equines, the most accurate being a weigh bridge. Calibrated weigh bridges come in a variety of models. The most common model is a portable type that fits into cars. Many feed companies or country stores now have these, offering regular weighing services so owners are able to accurately monitor their horse’s weight.

A weigh-tape is a cheap tool that is effective for monitoring weight fluctuations, as opposed to accurate weight of the horse itself. A weigh-tape measures the circumference of the girth area, but this does not consider fat distribution across other areas of the body; moreover, different brands will give very varied readings.

Body condition scoring is a subjective method of assessment which varies depending on the skills and training the individual has – however, this is an easy method for the horse-owner to carry out regularly at home to monitor any changes. At Bransby Horses we recommend using the 0-5 Body Condition Score (BCS) scale and assess the horse in three key areas: neck, abdomen and hindquarters before an average score is determined.

Body Condition Scoring is not a visual assessment, it’s important to physically get your hands on the horse’s body to make an informed assessment. A BCS of 2.5-3.0 is considered a healthy weight (for a majority of equines), anything below or above indicates the need for alterations to be made to exercise and weight management routines. For more details please see our Body Condition Score resource.

Effective weight-loss
Weight-loss regimes can be difficult for many owners, but it’s important to get it right to ensure your horse is fit and healthy. Consistent and gradual weight-loss is the most realistic and recommended programme and should be a balance of increased physical activity (wherever possible) and a reduction of calorie intake. For weight loss, an equine’s diet should be a total of approximately 1.5%[2] of the horse’s desired body weight per day – how this is achieved is heavily dependent on the practicalities of management styles, the facilities available and your vet’s advice. In some cases, a vet may recommend reducing the daily intake to 1% of their desired bodyweight for a short time only to trigger weight loss.

Grazing
Grazing needs to be of suitable length and type for the individual horse. Lush green pastures might be aesthetically pleasing to people, however, horses and particularly ponies are not designed to be grazing these areas. Rough grazing of poorer quality grass is ideal for most leisure horses, providing there is enough fibre for maintenance and not weight gain. Strip grazing can be used to limit grass intake provided enough space is available to prevent squabbling within the herd. Moreover, grazing muzzles are an effective and simple measure to reduce intake by up to 80%[3]. Muzzles shouldn’t remain on the horse for any more than 12 hours per day. Grazing must be of a suitable length for effective muzzle use and the muzzle should be fitted appropriately to prevent any rubs or sores developing. Introducing a muzzle should be taken slowly to ensure that the horse is comfortable with eating and drinking whilst wearing one.

Stabling or Dry-lot
If stabling or turning out your horse in an all-weather turnout area is achievable for even part of the day, this can effectively promote weight-loss. Whilst in these areas, a hay containing less than 10% non-structural carbohydrate (starch and sugar) should be fed[3]. This level can easily be reduced by soaking in clean water for up to approximately 12 hours. It’s highly recommended that owners have forage supplies analysed to confirm their nutritional content, to determine what dietary changes might need to be made to aid weight loss. Forage analysis services are offered by many feed companies for a small fee. In addition, whilst the quantity of forage is also being reduced, it’s vital to increase the time it takes for the horse to consume the ration. Horses have evolved to graze for 16-18 hours per day, and therefore, horses on restricted diets are likely to be left for periods without food, which could cause the onset of colic, stomach ulcers or unwanted stereotypical behaviours. To increase the time spent grazing conserved forages (such as hay or haylage) small-holed nets should be used or even double-netting to encourage the horse to work harder for his forage. Moreover, the daily ration can be split into several smaller meals distributed evenly through the day to reduce the time the stomach is empty[4].

Straw is very high in lignin – which is undigestible fibre and can be added to the diet and used as a belly-filler to increase the quantity of feed/chew time, but not the calorific value of the ration. Straw should only be offered to horses who have healthy teeth and introduced to the diet slowly to reduce any associated risks of impaction colic. Alternatively, many feed companies now produce a hay-replacer product containing chopped straw that horses can easily graze on to assist with weight loss.

Removing sweet and sugary treats and/or feeds is also helpful to promote weight loss. Whilst horses are on a restricted diet, they are likely to lack vital nutrients, so the addition of a ration balancer or vitamin and mineral supplement is highly recommended to ensure their diet is balanced. Supplements should be fed alongside a small quantity of low-calorie feed to carry the supplement, unless a low-calorie balancer is utilised.

Exercise
Exercise is just as important for weight loss as the diet itself. By increasing the physical activity of the horse, more calories are being burnt so less will be laid down as fat tissue. Exercise should be increased gradually to the overweight horse, they are often classed as being lazy, but in-fact they’re probably just struggling to cope with the additional weight placed upon their joints. Ensure the horse is fit enough to cope with the exercise you’re asking him to do, start by hacking at walk, or walking in-hand and build this time up to increase fitness before asking anything more of them. Increasing exercise for the obese companion horse can be difficult if they suffer from chronic lameness issues or other mobility issues. Any increase in exercise has its benefits, even just increasing the distance the horse has to walk from their feeder to the water trough has a positive impact.

Rugs
Horses have evolved over the years to naturally fluctuate their weights through the year to their advantage. Weight gained during the spring and summer months are laid down as fat reserves that can be used as an energy store during adverse weather and when grazing is sparse to help keep them warm. A horse that is carrying too much weight should not be over-rugged to allow these fat reserves to be utilised and benefit from the subsequent weight-loss.

Maintaining
Once a target weight has been achieved, the horse’s ongoing management will still need to be closely monitored to prevent him becoming overweight once again. If a horse has been overweight before, they have a higher risk of becoming so again – prevention is better than cure.

Summary
Equine obesity is an ongoing problem, and a battle faced by many horse owners nationwide. By making some minor changes as described above, it’s possible to encourage gradual weight loss and maintain an ideal weight throughout the year.

If you need any further information on weight management or equine obesity, please do not hesitate to get in touch with us.

Click here for a downloadable version of this information on Equine Obesity.

References: 1 – Menzies-Gow, N., Harris, P. and Elliot, J (2016). Prospective cohort study evaluating risk factors for the development of pasture associated laminitis in the United Kingdom. 2 – Frank, N., Geor, R., Bailey., Durham, A. and Johnson, P. (2010). Equine Metabolic Syndrome. 3 – Longland, A., Barfoot, C. and Harris, P. (2012). The effect of wearing a grazing muzzle vs. not wearing a grazing muzzle on intakes of spring, summer and autumn pastures by ponies. 4 – Dengie Crops Ltd. (2019).