As we know, practicing medicine means a lot more than simply prescribing medications. Instead, many equine conditions require a multimodal treatment approach, frequently including changes in diet and environment. Consider heaves, for example. Not only do horses benefit from either systemic (corticosteroids, bronchodilators, omega-3 fatty acids) or inhaled (corticosteroids, bronchodilators, cromones) medications, but also management changes. As described in the recently published ACVIM revised consensus statement on inflammatory airway disease of horses, using low-dust bedding and feedstuffs (e.g., changing to a complete pelleted feed rather than hay), improving barn ventilation to reduce respirable airborne particles, turning horses out 24/7, and soaking hay and avoiding hay nets if/when hay is offered are all equally important.
Similarly, peer-reviewed publications describing nutritional modifications for a variety of other common medical equine conditions abound. Consider some of the following recommendations when discussing a patient’s management with the owner. In many cases, small changes in diet can make a big difference in a horse’s life.
Insulin Resistance and Equine Metabolic Syndrome
It is now well recognized that many horses and ponies are not as sensitive to the effects of insulin as expected. In many cases, the hardier breeds, so-called easy keepers and ponies are more at risk to develop equine metabolic syndrome (EMS), which is characterized by altered insulin dynamics, obesity and chronic laminitis. With no medical treatment available for either insulin resistance (IR) or EMS, weight loss— approximately 1 to 2 percent of their body weight per week — is the primary target. Weight loss can be achieved by:
- Accurately assessing the horse’s body condition score (BCS) before, during and after the period of weight loss. This may seem like common sense to veterinary practitioners, but several recently published studies reported that owners still finding it challenging to determine their horse’s BCS. For example, one Australian research team described its experience with 10 Pony Club groups involving 229 horses and ponies. They reported that approximately 40 percent of owners significantly underestimated their horse’s condition — meaning they thought their horses were thinner than they actually were — whereas only 16% of owners overestimated body condition. Take the time to help owners understand how to assess a BCS. Encourage your owners to use readily available BCS charts to achieve/maintain a BCS of 5-7. Alternatively, have owners download easy to use apps for their smartphones, such as Healthy Horse.
- Decrease pasture intake but still allow turnout for exercise. This will necessitate using grazing muzzles or dry lots;
- Soak hay to reduce intake of water-soluble carbohydrates (WSCs) in addition to caloric restriction, recommends hay-soaking expert Cathy McGowan, BVSc, PhD, DEIM, Dipl. ECEIM, MRCVS, of the University of Liverpool’s Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, in the U.K. There are many ways to successfully soak or steam hay. Find out different ways based on a recent review of the literature here;
- Ensure horses are being offered no more than 1.25-1.5% of their body weight in forage (pasture and hay) per day; and,
- Encourage owners to have their hay analyzed to ensure soaking is sufficient to remove adequate WSCs while maintaining sufficient electrolyte levels and balance.
These dietary changes are not only beneficial to help manage insulin dysregulation but also address the laminitis frequently occurring in affected horses. Don’t forget to ensure owners are providing appropriate farrier care and using appropriate analgesics during flare-ups.
Equine Cushing’s Disease
Like IR and EMS horses, those with equine Cushing’s disease are frequently overweight and also often suffer from chronic laminitis. The above-described strategies for weight loss in IR and EMS horses are also usually appropriate for those with equine Cushing’s disease, including hay soaking. In fact, hay soaking/steaming will be doubly beneficial because it also reduces respirable air particles that are detrimental to older horses with heaves (COPD, equine asthma), common in older horses (like those affected with equine Cushing’s disease). Further, a hindgut buffer may be beneficial to help control the pH in the large intestine to help prevent the onset of additional bouts of laminitis.
Be certain to use all available resources supported by evidence-based medicine for the management of this common and painful, debilitating condition, including:
- Non-steroidal anti-inflammatory drugs;
- Intra-articular corticosteroids, hyaluronic acid, polysulfated glycosaminoglycans;
- Interleukin receptor antagonist protein (IRAP I and II);
- Oral avocado-soybean unsaponifiable (ASU) and omega-3 fatty acid supplements; and,
- Weight management (including routine exercise as described above).
Regardless of the underlying condition, be certain to highlight the following when discussing weight loss/management with owners:
- It is important to actually weigh hay rather than dolling out flakes. This important fact was emphasized in a recent article on the nutritional management of colic. Specifically, the study authors mentioned that individual flakes of hay vary in weight by as much as 1 to 2 kilograms (2.2 to 4.4 pounds). As a result, horses fed by the flake can be easily overfed.
- Caloric restriction and dietary modification alone is often not sufficient for weight loss — exercise is required. Hand-walking, longeing, long-lining, hill training, interval training (trotting for 30 seconds, recover for 30 seconds, repeat), and light hacks or trail riding are all good ways to start getting your horse fit and lose weight (as long as the horse is not suffering from a current bout of laminitis).
Finally, as recommended previously, get to know a reputable, knowledgeable, professional equine nutritionist or your local extension specialist. Refer your clients to these sources to help revamp their horse’s diet, tailoring each diet to your patient’s individual needs.