McCombs Equine Veterinary Services

Dr. Ann E. McCombs, MS, DVM
(815) 648-4471

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Estimating Horse Weight Accurately

Learn to Recognize the Signs of Laminitis

10 Tips for Preventing Colic

10 Tips for Caring for the Older Horse

Emergency First Aid Kit

Avoiding Impaction Colic

Don't Skip the Purchase Exam

Obesity and Equine Metabolic Syndrome

Strategic Deworming Program

Basic Biosecurity-Simple Steps for Keeping your Horse Healthy

Review your First Aid Kit

Equine Odontoclastic Tooth Resorption and Hyper Cementosis

Nutritional Myths

Estimating Horse Weight Accurately

How to Measure A team of Auburn University researchers recently compared methods of estimating weight in horses and found that one stood out as a more accurate approach.

"Knowing the body weight of a horse is important in many facets of horse care (i.e. dosing for dewormers and other drugs and determining feed rations)" said Elizabeth Wagner PhD, assistant professor in the department of Animal Science and lead author on the study.

The team weighed 145 adult horses on a portable livestock scale to determine their actual weight before the animals' weights were estimated using the 2 methods described here. Both methods underestimated the horses' weights but the point measurement gave the more accurate estimates (The point measurement underestimated weights by an average of 38 pounds. The weight tape underestimated weights by an average of 145 pounds).

1. WEIGHT TAPE     Encircle horse with weight tape as shown by A in diagram. Read estimated weight on tape.

2. POINT MEASUREMENT     Using a tape measure that measures in centimeters (cm), measure the heart girth (circumference of horse - A) and the body length (B). Plug those numbers into the following formula to determine horse weight in kilograms.

Horse weight (kg) = (heart girth)2 * (body length) / 11880

Example:     Heart Girth = 182 cm.      Body Length = 157 cm.

Horse Weight (kg) = 182 * 182 * 157 / 11880 = 438 kg

Horse Weight (lbs) = 438 kg * 2.205 kg/lb = 966 lbs.


Learn to Recognize the Signs of Laminitis*
Every day veterinarians across the country see hundreds of cases of laminitis, a painful disease that affects the feet of horses. Laminitis results from the disruption of blood flow to the sensitive and insensitive laminae within the foot, which secure the coffin bone to the hoof wall. While the exact mechanisms by which the feet are damaged remain a mystery, certain precipitating events can produce laminitis. Although laminitis occurs in the feet, the underlying cause is often a disturbance elsewhere in the horse's body.

As a horse owner, it is important to recognize the signs of laminitis and seek veterinary help immediately. Signs of acute laminitis include the following:

  • Lameness, especially when a horse is turning in circles; shifting lameness when standing
  • Heat in the feet
  • Increased digital pulses
  • Pain in the toe region when pressure is applied with hoof testers
  • Reluctant or hesitant gait, as if "walking on eggshells"
  • A "sawhorse stance" with the front feet stretched out in front to alleviate pressure on the toes and the hind feet "camped out" or positioned farther back than normal to bear more weight
Signs of chronic laminitis may include the following:
  • Rings in hoof wall that becomer wider as they are followed from toe to heel
  • Bruised soles or "stone bruises"
  • Widened white line, commonly called "seedy toe" with occurrence of blood pockets and/or abscesses
  • Dropped soles or flat feet
  • Thick "cresty" neck
  • Dished hooves, which are the result of unequal rates of hoof growth
If you suspect laminitis, consider it a medical emergency and notify your veterinarian immediately. The sooner treatment begins, the better the chance for recovery. For information about laminitis, ask your equine veterinarian for the "Laminitis: Prevention and Treatment" brochure provided by the American Association of Equine Practitioners (AAEP) in association with Bayer Animal Health, an AAEP educational partner. Additional information can also be found on the AAEP's website:

* Reprinted with permission from the American Association of Equine Practitioners.


10 Tips for Preventing Colic*
The number one killer of horses is colic. Colic is not a disease, but rather a combination of signs that alert us to abdominal pain in the horse. Colic can range from mild to severe, but it should never be ignored. Many of the conditions that cause colic can become life threatening in a relatively short period of time. Only by quickly and accurately recognizing colic - and seeking qualified veterinary help - can the chance for recovery be maximized.

While horses seem predisposed to colic due to the anatomy and function of their digestive tracts, management can play a key role in prevention. Although not every case is avoidable, the following guidelines from the American Association of Equine Practitions (AAEP) can maximize the horse's health and reduce the risk of colic:

1. Establish a daily routine - include feeding and exercise schedules - and stick to it.

2. Feed a high quality diet comprised primarily of roughage.

3. Avoid feeding excessive grain and energy-dense supplements. (At least half the horse's energy should be supplied through hay or forage. A better guide is that twice as much energy should be supplied from a roughage source than from concentrates.)

4. Divide daily concentrate rations into two or more smaller feedings rather than one large one to avoid overloading the horse's digestive tract. Hay is best fed free-choice.

5. Set up a regular parasite control program with the help of your equine practitioner.

6. Provide exercise and/or turnout on a daily basis. Change the intensity and duration of an exercise regiment gradually.

7. Provide fresh, clean water at all times. (The only exception is when the horse is excessively hot, and then it should be given small sips of lukewarm water until it has recovered.)

8. Avoid putting feed on the ground, especially in sandy soils.

9. Check hay, bedding, pasture and environment for potentially toxic substances such as blister beetles, noxious weeds and other ingestible foreign matter

10. Reduce stress. Horses experiencing changes in environment or workloads are at high risk of intestinal dysfunction. Pay special attention to horses when transporting them or changing their surroundings, such as at shows.

Virtually any horse is suspectible to colic. Age, sex and breed differences in susceptibility seem to be relatively minor. The type of colic seen appears to relate to geographic or regional differences, probably due to environmental factors such as sandy soil or climatic stress. Importantly, what this tells us is that, with conscientious care and management, we have the potential to reduce and control colic - the number one killer of horses.

For more information about colic prevention, ask your equine veterinarian for the "Colic" brochure provided by the American Association of Equine Practitioners in partnership with educational partner Bayer Animal Health. Additional colic information is available by visiting the AAEP's website:

* Reprinted with permission from the American Association of Equine Practitioners.


10 Tips for Caring for the Older Horse*
Because of advances in nutrition, management and health care, horses are living longer, more useful lives. It's not uncommon to find horses and ponies living well into their 20s and 30s. While genetics play a role in determining life span, you too, can have an impact.

You may think that turning your old-timer out to pasture is the kindest form of retirement. But horses are individuals. Some enjoy being idle; others prefer to be a part of the action. Whatever you do, don't ignore the horse. Proper nutrition, care and exercise will help the animal thrive. Follow these guidelines to develop a total management plan for your older horse:

1. Observe your horse on a regular basis. Watch for changes in body condition, behavior and attitude. Address problems, even seemingly minor ones, right away.

2. Feed a high quality diet. Avoid dusty and moldy feeds.

3. Feed your older horse away from younger, more aggressive ones so it won't have to compete for feed.

4. Feed at more frequent intervals so as not to upset the digestive system. Two to three times daily is best.

5. Provide plenty of fresh, clean, tepid water. Excessively cold water reduces consumption which can lead to colic and other problems.

6. Adjust and balance rations to maintain proper body conditions. A good rule of thumb is to be able to feel the ribs but not see them.

7. Provide adequate, appropriate exercise to maintain muscle tone, flexibility and mobility.

8. Groom your horse frequently to promote circulation and skin health.

9. Be aware that older horses are prone to tumors. Look for any unusual lumps or growths from head to tail as well as beneath the tail (especially on gray horses).

10. Schedule routine checkups with your equine veterinarian. Call immediately if you suspect a problem.

A quick response to ailments or injuries or a decline in fitness can keep your older horse from having a serious or prolonged setback. That means less worry for you and a better quality of life for your old friend.

For more information about caring for the older horse, ask your equine veterinarian for the "Older Horse" brochure, provided by the American Association of Equine Practitioners in partnership with educational partners Bayer Animal Health and Purina Mills. Visit the AAEP's website:

* Reprinted with permission from the American Association of Equine Practitioners.


Sample Emergency First Aid Kit
Your customized first aid kit should be accessible, portable and stored in a waterproof container. The kit needs to be stored in a controlled temperature. Medications need to be checked for expiration dates. Veterinary emergency contact numbers should be printed on the inside cover of your kit. Contact veterinarian for advice on how to proceed before administering any medications.
  •   Bandage materials: roll cotton, sheet cotton, quilts,   standing wraps, shipping boots, sanitary napkins,   Telfa (non-stick) pads, gauze pads, vet wrap,   diapers
  • *Ace
  • *Banamine
  •   Betadine scrub and Nolvasan solution
  • *Bute paste
  • *Antihistamine or injectable steroid
  •   DMSO solution
  •   Non-sterile gloves
  • *Steroid powder
  •   Needles and syringes
  •   Wound ointment
  •   Thermometer
  •   Saline
  •   Ichthammol
  •   Bandage scissors
  •   Duct tape
  •   Flashlight with batteries
  •   Plastic wrap
  •   Pliers
  •   Vaseline
  •   Poultice
  •   Towels
  •   Electrolytes
  •   Frog support for laminitis
  •   Alcohol
  •   Stethoscope
  • *Triple antiobiotic eye ointment
  •   Notepad and pen
  •   Hoof knife, pick and shoe pullers
  •   Instant ice
  •   Epson salts
  •   Clippers or shaver
  •   Spare halter and lead rope
First Aid Kit
* Obtain items from your veterinarian


Avoiding impaction colic by ensuring adequate water intake
Dehydration can be as much of a problem in winter as it is in the summer. No matter what time of the year it is, horses need to drink a minimum of 10 to 12 gallons of water a day to stay healthy. Water requirements increase if they are ridden. Horses worked in the winter continue to sweat, although it may not be as apparent because sweat evaporates quicker in the drier winter air. Many owners stop using electrolytes when it gets cold which lowers the salt levels in the diet and reduces the thirst response. Winter diets tend to contain less moisture when compared to fresh green grass. The combination of dry forage and decreased water intake increases the risk of impaction colic.

To aid in the prevention of impaction colic: (1) Provide moistened feed when possible, soak hay and beet pulp with water and add fresh fruits and vegetables with water to concentrates before feeding. You may add salt or a balanced electrolyte to the soaking water to make it less likely to freeze quickly. (2) Keep drinking water clean, fresh and unfrozen. Ideal temperature for drinking water is between 45 and 65 degrees. (3) Ensure horses are consuming adequate levels of salt. Access to a plain white salt block should meet this requirement for horses at rest in a cold environment. If horses are in work thru the winter, provide them with a balanced electrolyte.


Don't Skip the Purchase Exam*
Owning a horse can be a big investment in time, money and emotion. Unfortunately, horses seldom come with a money-back guarantee. That's why it is so important to investigate the horse's overall health and condition through a purchase exam conducted by an equine veterinarian. Whether you want a horse as a family pet, a pleasure mount, a breeding animal or a high preformance athlete, you stand the best chance of getting one that meets your needs by investing in a purchase exam.

Purchase examinations may vary, depending on the intended use of the horse and the veterinarian who is doing the examination. Deciding exactly what should be included in the purchase examination requires good communication between you and your veterinarian. The following guidelines from the American Association of Equine Practitioners (AAEP) will help ensure a custom-tailored exam:

  • Choose a veterinarian who is familiar with the breed, sport or use for which the horse is being purchased
  • Explain to your veterinarian your expectations and primary uses for the horse, including short and long-term goals (e.q. showing, then breeding)
  • Ask your veterinarian to outline the procedures that he or she feels should be included in the exam and why
  • Establish the costs for these procedures
  • Be present during the purchase exam. The seller or agent should also be present
  • Discuss with your veterinarian his or her findings in private
  • Don't be afraid to ask questions or request further information about your veterinarian's findings in private
The veterinarian's job is neither to pass or fail an animal. Rather, it is to provide you with information regarding any existing medical problems and to discuss those problems with you so that you can make an informed purchase decision. Your veterinarian can advise you about the horse's current physical condition, but he or she cannot predict the future. The decision to buy is yours alone to make but your equine veterinarian can be a valuable partner in the process of providing you with objective, health-related information.

For more information about purchase exams, ask your equine veterinarian for the "Purchase Exams: A Sound Economic Investment" brochure provided by the American Association of Equine Practitioners (AAEP) in association with educational partner Bayer Animal Health. Additional information can also be found on the AAEP's website:

* Reprinted with permission from the American Association of Equine Practitioners.


Obesity and Equine Metabolic Syndrome
Maintaining a healthy weight in horses and ponies is important because obesity can contribute to joint pain and pathology, insulin resistance, equine metabolic syndrome (EMS) and laminitis. Overweight equines are the result of overfeeding and inadequate physical activity, both of which are under the control of the owner. Recently, a diet has been described to help control calories and improve insulin sensitivity. Dr. Cathy McGowan tested the following recipe for obese/EMS horses:

1. Offer the horse the equivalent of 1.5% of his body mass each day in grass hay.

2. Divide the total daily hay into 2 hay nets, offering 1 in the morning and 1 in the evening. Soak the hay 8 to 12 hours before feeding to reduce water-soluble carbohydrates.

3. Offer a balanced vitamin and trace minereal supplement designed for use in conjunction with soaked hay.

4. Turn the horse out for at least 1 hour per day for exercise, ensuring he wears a properly fitted grazing muzzle.

5. Ensure the horse has constant access to clean water.

She found that horses included in this study lost an average of 6.8% of their body mass and showed significant improvements in body condition scores, belly circumference and insulin sensitivity after only 6 weeks of dietary restriction.

Testing for EMS and for Equine Cushings Disease (PPID) can be done by Dr. McCombs at your horse's stall side - don't wait until your horse suffers from painful laminitis.


Strategic Deworming Program

sample dewormersRecent literature has documented increasing dewormer resistance in common equine internal parasites. This problem is likely to be made worse with many clients still operating under the old belief that they should deworm every 6 to 8 weeks and rotate between families of dewormers. In some cases the horseman simply changes the brand name or the color of the box believing that they are rotating appropriately. The widespread availability of inexpensive over-the-counter anthelmintics has created a "hit or miss" approach that is expensive to maintain because of it's ineffectiveness, unnecessarily poisoning horses, potentially damaging the environment and causing parasite resistance.

The use of routine fecal egg counts (FEC) allows veterinarians and owners to decide which horses to deworm, with what product and when to deworm. When entire farms participate, resistance to specific dewormer classes may be identified on the property. Egg counts can identify dewormer resistance on individual farms through fecal egg count reduction tests (FECRT). A recent lecture presented at the American Association of Equine Practitioners convention emphasized the need for selective use of our remaining effective dewormers as necessary to reduce the formation of resistance. By following the recommendation of your veterinarian, you will save money, deworm effectively and only deworm the horse that requires deworming thereby ensuring the continued effectiveness of our current dewormer classes.

Beginning in 2011, McCombs Equine Veterinary Services Healthy Horse Program will include a FEC to determine your horses' parasite shedding classification (low, medium or high). Horses not enrolled may have a FEC sample collection by the owner, stable manager or the veterinarian. The samples need to be made fresh (within 2 hours), collected in plastic bags or gloves with the air removed, kept cold (refrigerated) and processed within 36 hours of it's creation to reduce potential larval development. The samples will be processed at McCombs Equine Veterinary Services In-House lab. The results of each patient's test will then be discussed with the owners and a schedule of recheck FEC and dewormings can be determined.

Foals up to 38 weeks follow a different schedule. Because they are just developing their immune response to parasite invasion, they need to follow a different protocol. The current recommendation is to deworm these little ones when they are 6 to 8 weeks old and follow this up with a FEC when they are 14 to 16 weeks old.

The effectiveness of the program depends on the continued cooperation of owners, stable managers and your veterinarian. When done correctly, this program will save money and the environment and assure us of effective dewormers into the future with much less possibility of developing parasite resistance.


Basic Biosecurity - Simple Steps for Keeping your Horse Healthy
We should all be concerned with the basics of cleanliness to prevent disease transmission in our barns - big or small. Here is a list of some precautions for your stable:
  • Work with your veterinarian to design an appropriate vaccination program for all horses in your care
  • Be sure that all horses entering your facility have up-to-date vaccinations as required and that they are free from communicable diseases
  • Isolate incoming horses for at least 2-3 weeks before allowing them exposure to horses currently on the grounds
  • Do not share water or feed buckets among horses
  • When cleaning or filling buckets, be sure not to let the hose nozzle touch the bucket itself
  • Assign a set of grooming tools to each horse in your facility and clean them regularly
  • Remove all manure and waste products to an appropriate location away from the barn
  • Take steps to limit horses' exposure to pest disease vectors like biting insects, barn birds and mice
  • Consult with your veterinarian about ongoing wellness care for your horses, including regular physical and dental examinations and a recommended deworming program
When horses become sick, here are some suggested methods of handling them to prevent infecting other animals in the barn:
  • Immediately isolate sick horses away from the herd
  • Follow disinfection techniques with all equipment that comes in contact with sick horses
  • Consult with your veterinarian about needed health care or vaccination protocols
  • Carefully sanitize all stalls, buckets, flooring and other equipment when a sick horse leaves the facility
  • Use a shallow basin full of properly mixed disinfectant for people to wash their shoes in before leaving the area containing sick horses
  • Offer hand sanitizers to any people who have touched sick horses before any healthy horses are touched
The effective use of a disinfectant is important when trying to prevent a disease outbreak or to control an outbreak after a horse is diagnosed. Here is a list of suggestions for correctly using these products:
  • Remove all excess debris or dirt from items to be disinfected
  • Wash the item first with a detergent such as laundry or dish soap
  • When applicable, use a high pressure washer or steamer to clean surfaces
  • Follow this washing by dipping the item in a disinfectant
  • For disinfection, you may use bleach, Roccal-D, Simple Green or other commercially available products. Be sure to follow label instructions for concentration and ventilation
  • Disinfection may be completed on items such as nylon halters, bits, lip chains, grooming equipment, shovels, pitch forks, shoes and clothing
  • Be sure to rinse the disinfectant off completely. Use clean water at least 2-3 times before you use the item to make sure the excess disinfectant is removed
Special considerations need to be taken when traveling with equines. The stress of shipping makes them more susceptible to disease as well as increased exposure to diseases they are not immunologically competent to handle. These suggestions should help to make your horses' travel safer.
  • Be sure to maintain an up-to-date (within 1 year) Coggins test for all your horses and carry it with you when you travel, along with a list of all current vaccinations, your vet's phone number and any medications needed. If you cross state lines or for many other equine events, you will also need a current health certificate (within 1 month).
  • Do not use common water buckets or feed areas
  • Do not share any equipment that may have touched another horse's eyes, nose or mouth
  • Keep daily temperature logs for your horses, particularly if they show signs of depression or are off feed
  • Isolate any sick animals immediately when signs are recognized


Review your First Aid Kit
Remember to go over your first aid kit and replace any expired, broken or used up items. Items left to freeze may not be good any longer. Read the product label to check. In an emergency, you don't want to have to depend on questionable products for your horses' health and safety.


Equine Odontoclastic Tooth Resorption and Hypercementosis
Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a recently recognized, painful condition that is most often found in older horses. This disease mostly affects incisors and canine teeth, but can affect molars as well.

In this disease, the body starts to reabsorb the affected teeth. The teeth react by laying down more cementum around and in the teeth to retain strength. This reaction is not enough to save the teeth and they become loose, fractured or fall out. This allows bacteria to enter the tooth and the surrounding structures, causing gingivitis and pulpitis. The cause is unknown.

Signs of EOTRH can include difficulty chewing, decreased appetite (especially for hay), rubbing the gums or incisors, pain on pressure on the teeth, irritability when ridden, weight loss, fractured or missing teeth and a swollen red or recessed appearance to the gums. This disease has a very gradual progression. Many horses are stoic and don't show outward clinical signs of discomfort. The goal is that regular, routine dental care will diagnose and begin treatment before the painful signs appear.

Visual appearance is confirmed by dental radiographs for a diagnosis. Most of the disease process occurs underneath the gums so radiographs are very helpful in diagnosis and prognosis. There is no known way to stop the disease process except to extract any affected teeth. After extraction, the horses have almost immediate relief. They do very well with a diet of senior feed and can even learn to graze using their lips to prehend the grass.


Nutritional Myths

There are a lot of age-old ideas on how to feed your horses. Some ideas have been handed down for generations by farm folk who fed working draft horses and mules. Other information has been fueled by the internet or feed companies that want to sell you the newest fad. In recent years, some of these ideas have been researched and proven wrong. It is important to know the difference between nutritional fact and fiction so that you can feed your horse correctly. Your veterinarian is a good reference when you have questions on nutrition.

Myth #1. Beet pulp must be soaked for hours or it will expand in the stomach, causing it to rupture. FICTION

This might seem logical since beet pulp will expand to many times its original volume when water is added. Science has shown that beet pulp can safely be fed without soaking. The equine stomach holds 2-4 gallons which is equivalent to 4.5 to 9.5 pounds of dry beet pulp. This is more beet pulp than most horses get in a single meal. Likewise, most food that enters the stomach passes to the small intestine within 15 minutes or less and it takes beet pulp longer than that to expand. Horses with access to water will drink enough to process any amount of beet pulp consumed and ultimately, the 40-50 gallon capacity of the equine digestive tract is more than sufficient to contain even a large meal of beet pulp.
However, there are situations where the horse is not voluntarily drinking enough water and dry beet pulp could contribute to an intestinal impaction. There are benefits to soaking beet pulp for short (3-4 hours) periods. Soaking makes it easier to chew, especially for those equine seniors with dental problems. It may also improve beet pulp's flavor and stickiness, making it easier to add supplements and medications. Also, the extra water will hydrate your horse when the winter cold makes drinking less appealing. Remember to throw away any leftovers within 1 day as it will start to spoil.

Myth #2. Fat provides "calm" calories while grain will make a horse "hot". MOSTLY TRUE

What makes a horse excitable is too much energy in the form of calories in the diet. Horses are unique in that calories fed in excess of their maintenance needs, can make them hyperactive. The source of the calories however, also plays a part in the energy level. Calories from cereal grains are digested mostly into starch which is broken down quickly into glucose. Elevated glucose alters hormones like insulin and thyroid hormone which can stimulate metabolism and cause excitability. Studies have shown that feeding fat doesn't result in the same type of rapid reaction so the blood sugar remains more stable. Still, if too much fat is fed and it does add calories beyond a horse's maintenance requirement, it could potentially cause excitability.

Myth #3. A show horse needs extra protein, especially if he's exercised a lot. IT DEPENDS

Exercise does increase the horse's protein requirement due to increased protein turnover in muscle (building and repairing tissue) and a small amount of protein can be lost every day in sweat; however, a performance horse's protein requirements don't increase to the same magnitude as they do in brood mares or growing horses.
Increased protein demands in performance horses can easily be met in most cases by just increasing roughage. When feeding more hay or pasture, the horse will also be getting more protein. A ten percent protein grain mixture is adequate for most mature pleasure horses who get grain.

Myth #4. Horses don't need a salt block if they get a commercial grain mixture with vitamins and minerals. FICTION

All horses need a source of salt (NaCl) added to their diet. Salt blocks work fine for horses that are idle or in light work but, for horses that do sweat a lot, it may be necessary to top dress the feed with salt. Commercial grain usually has 0.5 to 1% salt added but this is usually not enough to meet a working horse's daily requirements. An average sized horse has a maintenance requirement of about 1 oz. of salt per day. When horses are in hard work, add an additional 2 to 3 oz. of salt per hour of heavy sweating.

Myth #5. Feeding bran mash, especially after intense exercise, will keep your horse "regular" and prevent colic. FICTION

Wheat bran does not have a high fiber/laxative effect in horses the way it does in humans. It does have more fiber than corn, about the same as oats and less than that of hay. Horses do usually enjoy the flavor and consistency of a wet bran mash. It should be considered more of a grain supplement rather than a forage/fiber food. However, all brans, including wheat and rice bran, are very high in phosphorus. About 90% of the phosphorus in brans is in the form of phytate, which decreases the absorption of calcium, as well as copper, zinc and manganese. If you feed several pounds of wheat or rice bran to your horse daily, you'll need to give him supplemental calcium to balance out his diet. If you give your horse an occasional bran mash as a treat, you might be causing more harm than good if your horse's gastrointestinal system becomes upset due to the abrupt change in feed. All feed changes should be done over a few weeks and in small amounts.

Myth #6. Alfalfa hay can cause problems and is not a good choice for feeding horses. FICTION

Myths abound regarding feeding alfalfa hay to horses. Perhaps you've heard that feeding alfalfa can cause colic, founder, bloat or kidney failure. All false. Alfalfa hay or cubes are generally a good source of nutrients and fiber for horses. There is evidence that alfalfa hay combined with the mineral content of the water in western states can contribute to the development of a mineral deposit in equine intestines known as enteroliths.
Alfalfa will usually exceed a horse's protein/calorie requirement and may need to be fed on a limited basis rather than free choice. Unless you are feeding brood mares or youngsters with an increased caloric requirement, horses will generally be fat on a diet rich with alfalfa. You may combine a lower calorie grass hay to keep them occupied throughout the day. Good quality pasture can also be calorie rich so beware of the same potential for weight gain.

Myth #7. Horses shouldn't be fed round bales of hay, which are suitable only for cattle. FICTION

Depending on storage conditions, round bales can just be hay in a bigger package. Sometimes the outer layer is weather-damaged and the horses will rip and tear through to get to the quality hay inside. Select clean, fresh smelling bales and only feed them to groups of horses than can finish them in 3 to 4 days. Any hay, after being exposed to the elements, will begin to mold. Feeding hay from a round bale feeder designed for horses reduces waste.