By Dr. Heather Beach

Is your horse a picky eater? Here is a rundown of various causes for picky eating that you can work up with your veterinarian.

Dental exam

Horses will actually continue to eat in the presence of a lot of dental pathology. However, a thorough, sedated oral exam with a full mouth speculum and bright light is indicated in any case of poor appetite. Horses can fracture teeth relatively easily. Symptoms of a newly fractured tooth include reluctance to eat, chewing on one side of the mouth only, drooling, and dropping grain. Horses may prefer to eat hay only and may be reluctant to eat grain or vice versa in cases of dental pain. Other dental pathology that may be discovered with a thorough oral exam include periodontal disease (gum infections), loose teeth, or endodontic disease (cavities).

Systemic Illness

Any horse that is acutely not eating should have their temperature taken immediately and should have manure output noted. A horse with an elevated body temperature will feel sick and be off feed. A horse developing an impaction will have reduced manure output and decreased appetite. Often, other symptoms of colic do not appear with impaction-type colic until the impaction is very severe so paying careful attention to the early symptoms and seeking veterinary treatment early can help resolve an issue before it becomes a major problem. Horses that have more chronic poor appetite should have a complete blood count (CBC) and Chemistry panel performed to look for other evidence of systemic illness. This bloodwork will provide the veterinarian with information about organ function (liver and kidney) and can potentially draw attention to more serious conditions like neoplasia (cancer) or other severe illnesses that are causing the horse to lose its appetite. 

Gastroscopy

Once dental pathology and systemic illness have been ruled out, a horse with chronic poor appetite should ideally have a gastroscopy performed. To perform a gastroscopy your horse will be fasted overnight (at least 12 hours). This enables the stomach to be empty of feed material so that the horse can be sedated and have a long flexible camera passed into the stomach to have a look around. Gastric ulcerations may be seen. There are two types of gastric ulcerations—squamous ulcers and glandular ulcers. The squamous ulcers occur in the main portion of the stomach and respond to acid-reducing medications like omeprazole (gastrogard). The glandular portion of the stomach extends deeper all the way to the opening of the small intestines. Ulcerations in this part of the stomach are often more serious and more difficult to heal. We often use a combination of medications including omeprazole, misoprostil, and/or sucralfate to treat ulcerations in this part of the stomach. Oftentimes these cases can be refractory to treatment and require multiple rounds of medicating to heal. Without the gastroscopy we do not know which type of ulcers the horse has, nor how long we need to treat in order to resolve the issue. Sometimes on gastroscopy we may also find that the horse has a gastric impaction. Horses with gastric impaction will have a poor appetite because their stomach is chronically full with a hard food mat that never fully empties. Treatment for gastric impaction involves passing a nasogastric tube and administering Coca-Cola (diet and caffeine free, of course!). The acid in the soda helps dissolve the food mat and is generally effective at resolving the issue. Finally, we can sometimes see evidence of neoplasia (cancer) on gastroscopy and may have the opportunity to take small biopsies of suspicious tissue through the gastroscope in order to make a definitive diagnosis. 

Behavioral Causes

Some horses will have behavioral reasons for turning down food. Stress in their environment may make them reluctant to eat. If they are in a group turnout situation, they may feel stressed that they will be chased off the food by a more aggressive horse. Conversely, some very vigilant horses may be so worried about watching over the herd that they do not take time to eat themselves. Some horses will only eat their hay well overnight when the barn is quiet and there is less commotion. It is important to make horses feel comfortable in their environment. Monitor your horse in his environment and pay attention to his facial expressions. If the horse appears stressed or worried more often than not, something is not working for him in his living arrangements. Some horses thrive when they can see other horses in the barn, others will do better with more privacy. Paying attention to how the individual horses in your barn behave will help you determine their preferences. 

Palatability

Finally, horses have a preference for different flavors and textures just as we do. The most important part of your horse’s diet is the forage or hay. Some horses—if they have access to pasture or if they have been fed very lush, second cut hay—will turn their nose up at a more coarse, first cut hay. This will usually resolve after a couple of days of “tough love” and not giving in to feeding them their preferred hay. Many horses will become over-conditioned on lush second cut hay, so it is important to not fall into the trap of believing that very lush hay is “needed” for all horses. Certainly very poor quality hay is not ideal, but usually when horses are under-conditioned it is due to limited feeding of hay, not the quality of the hay being fed. Most commercial diets formulated for horses have had palatability testing done, however, every horse is different and very picky or suspicious eaters may have an aversion to certain products. If your horse isn’t eating his grain, the first thing that should be tried is to remove all supplements and medications. Very suspicious eaters will not be able to tolerate supplements in their grain and there is no point in buying a supplement if your horse will not eat it. Make sure the feed tubs are thoroughly cleaned to remove any old supplement or medication residue. Finally, small, frequent meals can be helpful for very picky eaters or distracted eaters who need to gain more calories. 

*This story was originally published in the March 2021 issue of The Plaid Horse. Click here to read it now and subscribe for issues delivered straight to your door!