Feeding Ill Horses
- Mar 3, 2005
When you're feeling under the weather, sometimes all you want is a nice, hot bowl of chicken soup. Other times, you might hunger for a full-course meal of roast beef, mashed potatoes, and steaming green beans. Even a mild injury that keeps you planted on the couch instead of sweating at the gym might change the way you think about food, urging you to cut back those desserts to hold your waistline in check. Likewise, your horse's dietary demands can change when he's ill or injured.
The good news is that if your adult horse is already eating a normal, balanced ration, you often won't need to alter that diet plan if he gets sick, says Sarah Ralston, VMD, PhD, Dipl. ACVN, associate professor of animal science at Rutgers University. While a sick horse's metabolic rate does typically increase, his activity level usually decreases, she explains. So the portion of feed that might normally go toward a schooling session is now redirected to aid the body's recovery efforts. In fact, since horses have such sensitive digestive systems, it's best to avoid making any drastic changes to an ill animal's diet, says Ralston.
That said, there are some situations where a change in ration can enhance progress toward good health or improve the horse's quality of life. For instance, stress--like that caused by surgery, orthopedic problems, or illness--increases the horse's B vitamin and vitamin C requirements. So, says Ralston, supplementing these vitamins might benefit an ill or injured horse.
If your horse is stall-bound from a lameness or orthopedic issue, he'll benefit from reduced grain intake and free-choice hay, notes Ralston. The lowered carbohydrates (grain) will keep his energy levels suited to confinement, and the increased roughage (hay) will not only keep his digestive system humming along, but will also help ward off the boredom of inactivity.
He's Gotta Eat
Another time to make dietary adjustments occurs when a horse stops eating for two days or more, says Ralston. In fact, it takes just 24 hours of fasting for the horse's body to begin catabolism--the process of breaking down body tissue to meet energy requirements. This can lead to muscle wasting, weight loss, and hypoproteinemia (abnormally low levels of protein in the blood). Fasting or lack of adequate nutrition for extended periods can also cause atrophy of the intestinal mucosa, general weakness, delayed healing of wounds and fractures, diarrhea, and reduced immune system function.
Obviously, then, it's important to keep a horse eating. If he isn't willingly consuming his usual ration, try these tactics:
- Let him graze; fresh grass often stimulates the appetite and might be more appealing to a sick horse than other feeds.
- Feed smaller amounts more frequently; an ill horse might be put off by large meals.
- Feed the same number of meals, but use smaller amounts of a more concentrated product with the same nutritive punch as his usual feed.
- Mix pureed carrots, applesauce, or molasses into his rations.
- Offer a smorgasbord of hays and let the horse choose what's most palatable to him; some sick horses might prefer alfalfa to grass hay. ("But don't let him overeat the alfalfa," cautions Ralston.)
- Soak the feed in warm water.
- Whip up a bran mash. (However, cautions Ralston, bran is neither a laxative nor a balanced meal. "It should only be used like chicken soup--soothing to horse and owner, good protein and fiber, but not for use long-term or in large amounts," she says.)
- Reposition the feed container to make sure your horse can reach it comfortably. (For instance, if your horse has an injured foreleg, it might be painful for him to eat feed on the floor, since reaching down places added weight on his forehand.)
- Make sure your horse has a quiet place to eat where he doesn't have to defend his meal from other animals.
- If your horse is in pain or has a fever, talk to your veterinarian about the possibility of giving analgesics for a short time, such as the non-steroidal anti-inflammatory drugs dipyrone or phenylbutazone (Bute). Reducing pain and fever can stimulate appetite.
Down the Tube
Unfortunately, it's not always possible to encourage a sick horse to consume an adequate diet. In those cases, veterinarians often turn to a nasogastric tube for aid. It can be inserted and removed several times a day, or it can be left in place by suturing the tube to a nostril. Either way, the horse generally can stay at home for this treatment, as long as it's only for a few days, says Ralston.
Depending on your horse's condition and his voluntary food intake, the veterinarian might use the tube simply to supplement the horse's intake (often to increase fluids or replace electrolytes). Or it might be used to provide full nutritional needs with a slurry of complete pelleted feeds or a complete liquid formula, says Ralston.
But there is a down side to tube feeding, she warns. Used long-term, it can irritate the nasopharynx. Plus, the liquid formulas lack fiber--and the treatment is expensive. "It should be used only as a short-term 'stop gap' until more normal feeds can be used," advises Ralston.
In the worst-case scenario, even tube feeding might not be enough. When a horse's digestive tract is too disturbed or diseased to absorb nutrition, intravenous (IV) "feeding" through a jugular catheter might be the only way to go. The treatment, also known as parenteral nutrition, requires sterile procedures as well as constant monitoring, so the horse must be hospitalized. That makes IV feeding an expensive option, with costs in the neighborhood of $400 per day.
Total nutrition can be delivered by IV. However, says Ralston, "It's more viable for partial supplementation, providing some energy, protein, and vitamins." Nonetheless, she adds, "It can make a real difference if done early, before the horse is literally starving and immunocompromised." In fact, prompt and proper use of parenteral nutrition has been credited with saving many a horse's life.
Five Special Diets
Besides cases of injury-induced inactivity and instances where a horse does not or cannot eat enough on his own, there are other specific disorders where therapeutic nutrition can benefit your horse. Following are five prime examples.
1. Severe burns, trauma, sepsis--These health dilemmas cause the horse's metabolic rate to rise. Also pushed upward are fat mobilization and utilization, protein catabolism, and utilization and excretion of vitamin C and the B vitamins, explains Ralston. Because of this, the horse's requirement for energy, protein, fluid, and water-soluble vitamins might be as much as 100% above maintenance needs, she adds.
In these cases, Ralston recommends feeding your horse a high-protein (14-16%), high-fat (7-10%) ration, supplemented with B-vitamin complex, vitamin C, and possibly vitamin E. Feed should be easy for the horse to consume. Suitable rations might include legume-mix hay, pellets or extruded feeds in slurry form, and supplements given orally, by nasogastric tube, or by IV.
2. Kidney (renal) failure--In horses with renal failure, calcium crystals that would normally be excreted in the urine instead accumulate in the kidneys, which could lead to kidney stones. Restricting the horse's intake of calcium to a maintenance level (0.4-0.6% of the total diet) can help the condition, says Ralston. In severe cases, you might need to restrict intake of phosphorus (0.2-0.4%) and protein (8-10%). She recommends avoiding alfalfa hay as well as wheat or rice bran. Instead, feed grass hay and plain grain, such as corn.
3. Liver (hepatic) failure--The horse's liver produces glucose (the principal form of energy) from non-carbohydrate sources, such as fat and protein. It also stores vitamins A, D, and E, and it cleanses the body of metabolic byproducts. When a horse has hepatic failure, you can help ease stress on the liver by reducing its need to produce energy and by lowering the wastes to which it is exposed.
To do this, you need to provide adequate energy in a way that doesn't require liver metabolism. That means providing feeds with a high glycemic index (that is, the glucose is more readily available to the body), says Ralston. Likewise, added B vitamins (particularly thiamine and niacin) and short-branched chain amino acids (such as leucine, isoleucine, and valine) can be helpful.
The horse's ration should contain no more than 5% fat and 8-10% protein. In particular, avoid tryptophan and aromatic amino acids (which are present at high levels in legumes and soybean meal) and added fats, says Ralston. Instead, opt for high-quality grain (particularly corn), plus grass hay and supplemental vitamin C and the B vitamins.
4. Cushing's disease (pituitary dysfunction)--Horses with Cushing's disease don't tolerate glucose as well as a young, healthy horse, so you should restrict their intake of sugars and starches. On the other hand, these horses have higher requirements for vitamin C and the B vitamins.
5. Post-colic surgery--A horse that has had relatively simple colic surgery that didn't involve intestinal resection (removal) should be started back on his normal feed as soon as possible, says Ralston. However, she adds, the horse should be fed small amounts frequently, gradually increasing the serving size until he's back to his usual routine. (This assumes that his original diet was not a cause of the colic.)
If a resection was required, feeding can get complicated, notes Ralston. Soaked hay cubes or complete pellets, or liquid nutrition products might be recommended. Requirements for fat, protein, fiber, and various vitamins might change from normal. Your best move with these horses is to work with your veterinarian--ideally in conjunction with a veterinary clinical nutritionist--to create diet plans for immediate post-op nutrition on through recovery.
Ralston cautions that any time major changes are needed in your horse's diet, you should make the switch gradually. Start by swapping out just 20-25% percent of his usual feed for the new feed. Then slowly increase the amount of new feed while decreasing the amount of the old feed over the course of two to four days, until the change is complete.
Something's Better Than Nothing
When your horse is sick, your veterinarian is usually your best ally. And your veterinarian should be the first one you turn to for advice relevant to your horse's specific situation. Unfortunately, says Ralston, many veterinarians don't possess in-depth knowledge about critical care or therapeutic nutrition. If this is the case with your veterinarian, consider contacting an equine nutritionist. While few veterinary schools have nutritionists that specialize in equine nutrition, Ralston notes that you can find one of these specialists through the American Academy of Veterinary Nutrition (www.aavn.org; click on Nutrition Resources, then Large Animal Nutrition Services) or the Equine Science Society (www.enps.org; mouse over "Links," then click on "Virtual Experts").
The bottom line, says Ralston, is that it's better to make sure your ill horse is being fed something, even if it's not the ideal ration, rather than nothing at all. Because no matter what's keeping him down, he'll need nutrition, along with your tender loving care, to get back to normal again.
About the Author
Sushil Dulai Wenholz is a free-lance writer based in Lakewood, Colo. Her work appears in a number of leading equine publications, and she has earned awards from the American Horse Publications and the Western Fairs Association.