With the glut of the best summer grass behind us and the cold weather yet to kick in, it’s perhaps to be expected that so many horses and ponies look a little on the plump side at the moment. Yet the prevalence of overweight equines appears to be a year-round problem — and one of growing proportions.

In a recent National Equine Health Survey, conducted by the Blue Cross, 17% of horses and ponies were reported to be overweight. That’s more than double last year’s figure. Furthermore, as many as one in three horses were assessed by their owners as “obese” in an Animal Health Trust (AHT) survey published in the Equine Veterinary Journal in February.

These figures suggest that excess weight gain is more than just a seasonal blip that will right itself when winter takes hold. The reality is that many horses and ponies are not only carrying more condition than they need to into the colder months, but are emerging in the spring with their surplus fat stores still intact.

Piling on the pounds

According to the Blue Cross, the horse’s metabolism is designed around an annual weight fluctuation — plentiful forage in the summer is converted to fat, to ensure survival in the colder months when there is no grass. While few horses nowadays need or use these winter fat stores, this metabolic mechanism still operates.

“Today we have fat horses entering the winter whose bodies are preparing for starvation, yet the ‘lean’ period never arrives,” states the charity’s website. “In many cases, horses continue to put on weight at a time when their bodies are designed to be losing it.

“The confusion that results contributes to an unfortunate trilogy of undesirable events, often called equine metabolic syndrome: obesity, insulin resistance and increased circulating cortisol. This can, in many cases, spark a serious bout of laminitis.”

The modern equine lifestyle means that horses typically burn fewer calories keeping warm than their wild counterparts.

H&H vet Karen Coumbe explains: “Although animals in the wild may eat more in summer to build up reserves, this is no longer relevant for most horses.

“For a start, our winters are no longer always that cold. More crucially, however, many horses are not exposed to the extremes of wintry weather. They are stabled with a plentiful supply
of warm rugs, so they do not necessarily need extra fat reserves.”

Kath Urwin, manager at the Blue Cross’s Rolleston centre, adds that horses tend to stand around for longer periods in winter.

“It’s much harder with stabled horses,” she says. “We want them to be eating for as many hours as possible for their digestive health and to prevent boredom. Yet leisure animals don’t work as hard these days as they did in the past.

“Many people enjoy feeding their horses in winter, as horses look forward to their meals,” adds Kath. “With rugs and two, perhaps three, feeds a day, it’s easy for weight to stay on.”

A knock-on effect

This persistent plumpness, explains Kath, can have a knock-on effect in the new year.

“We would expect horses to be in an ideal condition or a little over at this time of year” she says.

“But if a horse remains overweight through winter, there’s no room for the natural weight gain in spring and summer.”

Many owners are becoming less comfortable with the normal process of weight gain and loss, says Kath.

“We generally want our horses to look the same in February as in September,” she explains.

“If a horse is stabled and you’re controlling absolutely everything — monitoring his turnout, weighing hay and measuring feed — it’s fine to keep him at the ideal weight all year. But it’s OK for a horse to be leaner coming out of winter, especially if he is field-kept all-year-round. It only takes a matter of weeks out at grass before the condition returns.

“People are reluctant to let their horses drop weight in winter, but it’s very natural,” she adds.

The right balance

While the effects of excess weight on the bones and joints are less well-documented, it is common knowledge that prolonged periods of obesity are associated with a large number of associated health risks — whatever the season. So how can we get the balance right in winter?

“Now is a good time to assess and plan ahead,” says Kath, adding that achieving weight loss is far easier in the colder months when the horse’s internal mechanisms are already working to that effect.

“Recognise if your horse is overweight and try to ensure he loses condition gradually over the next six months.

“If he’s in ideal condition at the moment or a little underweight, aim to maintain that.”

Woolly winter coats and thick rugs can make it harder to gauge condition, but Karen suggests regular use of a weigh tape for more accurate monitoring.

“Every horse and pony should be fed as an individual, according to their type and workload,” she says. “Rely on suitable roughage to provide warmth in colder weather, which means plenty of hay or haylage. Roughage should be the foundation of any horse’s diet, even those in hard work.

Many will need little else apart from vitamins and a supplement containing trace elements and minerals, as necessary.

“The key message is that it is best not to overfeed on a just-in-case basis.”

This article was first published in Horse & Hound magazine (9 October 2014)

Are you ready for winter? Feeding your horse