Aqueos - How to measure your horse's weight

Aqueos - How to measure your horse's weight

Why is it important to know your horse or pony’s weight?

Knowing your horse or pony’s bodyweight is an important part of good animal husbandry. Whether you need to calculate the amount of feed or roughage to give to your horse, you need to administer worming treatment, or you need to give a medication which has been prescribed by your veterinary surgeon, having an accurate weight for your horse will ensure that they receive the correct amount of feed, wormer, or medication.

Why do we need to monitor horses’ and ponies’ weight?

Equine obesity is a growing problem, and of growing concern to veterinary and welfare professionals, especially as it is not well recognised by horse owners. In many cases, we are therefore monitoring horses’ and ponies’ bodyweight because we are concerned that they are carrying too much weight, and we want to see them lose some. Equally important, however, is monitoring the bodyweight and condition of those horses and ponies who struggle to maintain their bodyweight – whether that be age-related or due to other health conditions.

In the wild, horses’ and ponies’ bodyweight naturally fluctuates over the seasons in response to the availability of food (grass). Domesticated equines do not have to struggle to find food because their owners provide for their needs throughout the year, with a ready supply of grass and hay or haylage, and concentrate (bucket) feed if required. The effect of this is that most horses and ponies will not have the natural fluctuations in bodyweight over the year, as we like them to look “in good condition” all year round. In some cases, bodyweight creeps up year on year, resulting in horses and ponies becoming overweight or even obese in some cases. 

What are the different ways to measure the weight of your horse or pony?

There are different ways to measure a horse or pony’s weight, and some are more accurate than others:

  • weigh bridge – the most accurate method
  • weigh tape – widely available and easy to use
  • using a formula – can be more accurate than a weigh tape but requires some mathematics!

Weigh bridges

If you are lucky enough to have access to a weigh bridge, this is the most accurate way to measure a horse or pony’s current bodyweight, and to monitor changes over time. Many equine veterinary practices will have a weigh bridge at their clinic and may even be able to bring a mobile weigh bridge out to your own premises. Alternatively, some horse feed companies can bring a weigh bridge out to yards for weight and feeding advice clinics. If either of these options are available to you, do make use of the service, as it is much more accurate than using a weigh tape or using an equation to calculate your horse or pony’s weight.

Most horses will be happy to walk onto a weigh bridge with encouragement; they are low to the ground and easy to step on and off. Often it is easier if the weigh bridge is against a wall so that there is only one side which you need to stop them stepping off. Weigh bridges must be placed on an even surface to work properly, so think about where you will ask your veterinary practice or feed company to set the weigh bridge up if they are coming to the yard. There is sometimes a requirement to have a reasonable number of horses to be weighed in order to bring the equipment to the yard, so get together with those on your yard to organise a weigh-in day, perhaps a couple of times a year, e.g. spring and autumn.

Weigh tapes or using a formula to calculate bodyweight

If you do not have access to a weigh bridge, or you want to monitor your horse or pony’s weight in between weigh-ins, you can either use a weigh tape, or a measuring tape and mathematical formula to calculate your horse’s weight. With either of these methods, make sure your horse is standing square before you start.

Weigh tapes are widely available from feed merchants, tack shops and online. The benefit of a weigh tape is that it is quick and easy to use, so you can easily measure your horse’s weight every 2-4 weeks throughout the year. A weigh tape is placed around the girth area, from the lowest point of the withers to as close as possible behind the elbow. There is often a horse side and a pony side, depending on the type of weight tape you are using – so make sure you’re using the right one!

If using a weigh tape for monitoring purposes, the same person should use the same weigh tape each time a measurement is taken, ideally at the same time of day, and you must be sure to place it in the same place each time.

Alternatively, the established mathematical formula to estimate body weight in mature horses is:

weight(kg) = (heart girth x heart girth × body length) / 11,880

To use this formula, use a measuring tape to take the horse or pony’s heart girth measurement in centimetres (from the highest point of the wither going to just behind the elbows), and the body length distance (from the point of the shoulder to the ischial tuberosity i.e. the point of the hip at the side of the tail) in centimetres, and then calculate the weight using the formula above.

Body Condition Scoring in Horses

Equally as important as recording a bodyweight in kilograms for your horse, is to learn how to body condition score your horse, as this provides useful information about whether they are carrying too much or too little weight. Different body condition scoring scales are available, but you should stick to the same scale each time once you are using it. The most common scale used is 0 (very poor) to 5 (very fat), and involves feeling for the amount of fat present in three different areas:

  • neck
  • back and ribs
  • pelvis

Body condition scoring charts are widely available online or alternatively from your feed merchant.

Take home message

Knowing and monitoring your horse or pony’s weight is an important part of their care, and it is recommended to check and record their weight every couple of weeks if you are able to, to quickly identify patterns of weight loss or weight gain.

Article written by Dr Jessica Putnam BVMedSci(Hons) BVM BVS(Hons) MRCVS – 23nd August 2021