Does Your Senior Horse Have EOTRH?

Today, our horses are living longer and healthier lives. With a longer life span we encounter additional challenges to keep our geriatric horses comfortable. One common condition in the older horse population is EOTRH (Equine Odontoclastic Tooth Resorption and Hypercementosis).

Photo Courtesy PugnoM on Flickr

What is EOTRH?

EOTRH primarily affects the incisors, although canine teeth and cheek teeth can also be affected. The process is painful, with some teeth resorbing their roots and/or lying down extra cementum, which causes the roots to appear bulbous.

EOTRH is suspected based on dental examination and definitively diagnosed with radiographs. Some early signs of disease include recession and swelling of the gums. In more advanced cases, the incisors also become loose, with draining lesions around the gums. EOTRH is insidious and painful. Horse owners may notice that affected horses are sensitive to placing the bit in the mouth or become unwilling to grasp hard treats such as carrots. As prey animals, horses may only exhibit subtle signs of discomfort. The cause of EOTRH is unknown and the disease process may be underway before clinical signs are noted during an oral exam.

How is EOTRH treated?

Unfortunately, we lack treatments to prevent or stop EOTRH. Although it may seem drastic, extraction of affected teeth is the best way to manage this condition and keep horses comfortable. Because of the advancements in equine dentistry, extraction is often possible to perform in the field. Radiographs provide valuable information about the severity of disease and help your veterinarian plan for the extractions.

For extractions, the horse is be sedated and receives anti-inflammatories. Nerve blocks and local anesthesia are vital to minimize discomfort. Depending on the individual horse, extractions may be staged, with more severely affected teeth extracted first. Typically, EOTRH eventually affects all incisors, so horses having more severely diseased teeth extracted first may require additional extraction sessions.

After extraction, radiographs are used to confirm that no tooth fragments remain. Depending on how many teeth were removed, some veterinarians will close the gums with suture, although these often fall out within a few days. Post-op care includes a soft diet, anti-inflammatories, and antibiotics. Flushing the mouth with dilute chlorhexidine solution can also aid in healing.

What is the prognosis for EOTRH?

Horse owners observe that their horses are noticeably happier within just a few days of extraction- proof that EOTRH teeth are painful! Providing that the horse has adequate remaining cheek teeth, permanent dietary changes after extraction are not necessary. Without incisors, some horses may allow the tongue to stick out slightly, but are still able to graze and consume hay.

Photo Courtesy Public Domain Photos via Flickr

Benefits of Gastroscopy

Most horse owners are familiar with equine gastric ulcers, or EGUS (equine gastric ulcer syndrome).  Gastric ulcers are extremely common in horses and likely underdiagnosed. Because horses evolved as grazing animals, their stomachs are designed for continual digestion and eating, continually secreting stomach acid. Management of the modern horse often prevents continual grazing, so periods of time without access to forage allow stomach acid to contact the stomach lining, causing ulcerated areas. Common risk factors include periods of time with an empty stomach (such as stalled horses without grazing access), stress (training, showing, travel), and administration of non-steroidal anti-inflammatories (phenylbutazone and banamine).

The gold standard for diagnosis is gastroscopy, where your veterinarian will examine the stomach and document findings with photos. Gastroscopy allows us to assign a score of severity to the horse’s ulcers as well as demonstrate healing following treatment. Recent technological advances have made this diagnostic modality available in the field, so gastroscopy can now be performed on the farm instead of trailering in to the clinic.

After you and your veterinarian have decided that gastroscopy is indicated for your horse, the most important part of the gastroscopic exam is patient preparation. Preparation requires fasting your horse for about 20 hours before the exam to ensure your horse’s stomach is empty. If there is food remaining in the stomach, your veterinarian will not be able to perform a complete examination. Frequently we recommend applying a muzzle to your horse during fasting since some horses will ingest shavings or straw. Water must be removed 3 hours prior to gastroscopy.

At the appointment, your veterinarian will sedate your horse to allow passage of the scope. The scope is passed up one nostril and to the back of the throat, when your horse will swallow it. During this process, the back of the throat can also be examined. After swallowing, the scope is passed down the esophagus (also examined) and then into the stomach. The upper portion of the stomach is called the squamous/non-glandular portion, based on the cell type composing the lining. The lower portion of the stomach is the glandular portion, where stomach acid is secreted. These 2 areas are divided by a  demarcation called the margo plicatus. Ulcers are most commonly found on the squamous portion of the stomach along the margo plicatus. The entire stomach is examined, including all the way to the exit of the stomach (pylorus) and ideally including the beginning portion of the small intestine (duodenum). A score is assigned to your horse based on location of ulcers and the severity of ulceration, ranging from 1-4. Your veterinarian will then work with you to determine the most appropriate treatment for your horse based on this exam. Ideally, the horse is re-scoped following treatment to ensure adequate healing and response to treatment.

MVS is excited to offer gastroscopy to enable appropriate diagnosis and treatment of EGUS, keeping your horse feeling and performing at his best. Contact us today if you’re interested in gastroscopy or would like to learn more.

Meet the MVS Staff: Spotlight on Dr. Kate Baer

Dr. Kate Baer is a 2012 graduate from the University of Minnesota College of Veterinary Medicine.  She completed a one-year internship with an equine referral and ambulatory practice in New Jersey, and then spent several years in Pennsylvania with a racetrack and ambulatory equine practice. In 2017, she attained certification in veterinary acupuncture through the Medical Acupuncture for Veterinarians. Dr. Baer joined MVS in 2019 and loves being a part of such a great team.

Dr. Baer appreciates the challenge and variety of equine ambulatory medicine. Her professional interests include geriatric horse care, dentistry, wound management, acupuncture, emergency medicine, and podiatry. Dr. Baer enjoys building relationships with clients and their horses, while working together to decide the best approach for each individual horse. She has also organized several educational seminars in the community for 4H, Westernaires, and Pony Club kids – previously in-person and now in an online format.

Outside of work, you will find Dr. Baer riding her off-the-track Thoroughbred, Liam, acquired during her days of racetrack practice in Pennsylvania. She hopes to return to the show ring this spring. She also takes full advantage of Colorado’s outdoor activities, including hiking, snowshoeing, rock climbing, mountain biking, and skiing. In rare moments of downtime, she also enjoys reading, foreign languages, cooking, and baking.

Pictured with Dr. Baer is Nora, vet truck dog in training.

Dental Xrays for Horses? Of course!

Dental radiographs (Xrays) are a routine procedure for us humans at the dentist’s office, but they are also invaluable for equine dentistry. As equine dentistry has significantly advanced in recent years, improvements in portable radiography equipment have dramatically increased the quality and diagnostic capability of our imaging. 

Findings on an oral exam that would indicate the need for dental radiographs include fractured teeth, loose teeth, diseased incisors, or evidence of sinus infection, such as nasal discharge. The portion of the tooth that can be visualized in the mouth is called the clinical crown, but there is significant length of tooth, as well as the roots, hidden beneath the gum line. Radiographs are the best way to evaluate the entire tooth while working in the field. They can identify disease that may not be readily apparent on an oral examination – such as infected or fractured tooth roots. Radiographs can help us decide if a tooth needs to be extracted and plan the best approach for extraction. Serial radiographs are helpful to monitor suspicious teeth over time. 

Preparing your horse for dental radiographs is much like preparing your horse for routine dentistry. Appropriate sedation ensures your horse is adequately relaxed and still so that we can capture good images. Depending on the area of interest (sinus, incisor teeth, or cheek teeth), your horse may have his mouth open for images taken at varying angles. We also have an intra-oral plate, similar to what you encounter with your own dentist. Intra-oral plates are great for imaging the incisors, as well as focusing on just few cheek teeth at a time while avoiding overlapping teeth of opposite sides. Our xray equipment allows us to take high-quality images in the field with the images immediately available for review. See below for some interesting Xrays.

Intraoral radiograph. The dark area is an abscess in the mandible (lower jaw) which developed secondary to an infected canine tooth.
Intraoral radiograph of 2 fractured incisors following trauma. Both teeth were extracted.
Red arrow is pointing to a “fluid line.” A sinus infection has filled the sinus with fluid. The nose is toward the bottom of the image, the horse is facing to the left, and you are looking at the horse’s head in profile.
The horse’s nose is pointed toward the right side of the image, showing the upper cheek teeth. The roots and tissue surrounding tooth 9 are abnormal. This horse had a history of one-sided malodorous nasal discharge. The diseased tooth was extracted.


Is your horse current on his rabies vaccination?

Rabies is caused by a virus that infects mammals and is spread through the saliva/bites by infected animals. The virus exists in several wild animal reservoirs, most commonly bats, skunks, raccoons, and foxes. After the virus is transmitted via bite, it replicates in the muscle at the site of the bite, and then travels to the central nervous system (brain and spinal cord). The virus continues to replicate in the central nervous system and then spreads through the rest of the body, including the salivary glands, which then allows transmission to other susceptible animals.

Is rabies a problem in Colorado?

In 2019, there were 173 lab-confirmed cases of animal rabies in Colorado, including canine, feline, and camelid cases. So far in 2020, Colorado has seen 71 lab-confirmed cases of rabies, including in a dog, goat, sheep, and bull. It is important to remember that because rabies is endemic in bat, skunk, and raccoon populations, these numbers don’t accurately represent the true prevalence of this disease.

What does rabies look like in horses?

While mention of rabies conjures images of a frenzied animal frothing at the mouth, clinical signs in the horse can be extremely variable, so many people may be potentially exposed before a diagnosis is made. Non-specific signs of rabies in horses can range from colic and lameness to fever and depression. There is no available testing to diagnose rabies in the live horse. When examining an un-vaccinated horse exhibiting bizarre behavior or neurologic signs, your veterinarian must consider rabies as a potential diagnosis. Signs in an infected horse progress rapidly, usually leading to death within 5-7 days. Rabies is always fatal in an unvaccinated horse.

The rabies vaccine is a core vaccine for horses, according to the American Association of Equine Practitioners (AAEP). A core vaccine is one that is essential for every horse, regardless of the horse’s lifestyle. Rabies is a FATAL disease but it is preventable through annual vaccination by your veterinarian. Because human infection is also fatal, rabies vaccination in domestic animals is a matter of public health. Any person who may have potential exposure to rabies should immediately contact their health provider.

Protect your horse- and yourself! Be sure to keep your horse’s rabies vaccination current, and don’t forget to vaccinate your barn cats and dogs!

Should You Microchip Your Horse?

Microchips: an easy, indisputable way to definitively identify a horse. In situations such as evacuations due to natural disasters or horse theft, it’s easy to see how microchip identification is invaluable. Other forms of identification are more subjective than a unique microchip number- markings change with time, tattoos become more difficult to read, and brands can be altered.

A microchip can also serve as proof of ownership, deter fraud in the sale of a horse, and identify at-risk horses at auction. But did you know the microchipping is also replacing older identification methods in breed registries? Did you know that many competitive organizations now require microchips?

Since 2013, the FEI has required microchips for competing horses. As of 2017, the Jockey Club requires microchipping for registration of Thoroughbred foals. The USEF and USHJA have required microchips since 2019. The AQHA is encouraging microchipping through the AQHA Microchip Pilot Project. The European Union has required microchips for foals since 2009. RPSI, Norwegian Fjord, and Oldenburg breed registries require microchipping.

The process of getting your horse microchipped is simple. First your veterinarian will scan your horse for an existing chip. Providing a chip is not found, your veterinarian will clean and prep the location for microchip placement. The standard location for placement is on the left side of the neck, halfway between the poll and the withers, within the nuchal ligament of the neck. The microchip is then scanned before placement to make sure the chip is read correctly. Each chip has a 15-digit unique number. The chip is inserted into the site and scanned again after placement to ensure it is read properly. Most horses tolerate this quick procedure very well, although the site can numbed with an anesthetic prior to chip placement if desired. Please contact us if you are interested in getting your horse microchipped. This procedure can be easily added to your horse’s next preventative care visit.

See the following links for more information on microchipping and show requirements:

https://files.usef.org/assets/WU5vkmldZDg/microchipping-faqs.pdf

https://equinemicrochiplookup.org/

https://www.aqha.com/-/aqha-microchip-pilot-project

https://www.ushja.org/competition/rules-and-proposals/microchipping-101

How does the smoky air affect my horse?

While the current wildfires are at some distance from us, we have not been spared from widespread smoke and poor air quality over the last few weeks. Just as poor air quality can be an irritant for us, it can also affect your horse. Unhealthy air contains irritants that can affect our eyes and nasal passages and may have a greater impact on those – both human and equine – with pre-existing respiratory conditions.

Smoke is composed of carbon monoxide, carbon dioxide, soot, nitrogen oxide, particulates, and trace minerals, as well as the primary source being burned (wood, vegetation, plastic, etc). The smoke from wildfires is high in particulate matter, which is problematic because of its extremely small size. Particulate matter easily travels to the smallest airways of the lungs, causing irritation and damage. For humans and horses, it can cause coughing, nasal discharge, and increased respiratory effort. It can also interfere with the normal defense mechanisms of the respiratory tract, decreasing immune function and the ability of the lungs to clear routinely encountered foreign materials. Horses with pre-existing respiratory conditions, such as heaves and allergies, are more sensitive to poor air quality.

How do I know if it’s safe for my horse to work?

The Air Quality Index (AQI) is the Environmental Protection Agency’s daily grade of air quality. The AQI accounts for five major pollutants: ground-level ozone, particle pollution (particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Air rated as “good” has an AQI <50. Today, August 17, 2020, Golden has an AQI of 57 (moderate), stating that air quality is acceptable, although there may be a risk for those who are more sensitive to air pollution.

Although there are currently no recommendations specifically for horses based on AQI, there are guidelines available for human athletes. The guidelines suggest removing sensitive human athletes from outdoor competition when AQI is >100 and removing all athletes from outdoor competition when AQI > 200.

What can you do to help your horse?

Be conscious of the air quality index and conditions. Go to https://www.airnow.gov/aqi/ to find the AQI in your area.

Limit exercise when smoke is visible.

Ensure adequate clean water is always available to your horse.

Limit exposure to additional dust- consider soaking hay prior to feeding.

Seek veterinary attention if your horse is showing any signs of respiratory difficulty or distress.

How to Select a Concentrate for Your Horse

With the variety of different feed and supplement choices available, it can be overwhelming to make decisions regarding your horse’s diet. It is important to remember that horses are grazing animals, designed to spend much of their day eating forage. Forage (grass and/or hay) should comprise most of your horse’s diet, at a rate of about 2% of his body weight per day. Of course, the nutrient profile of different forage sources can vary as well, so a hay analysis can provide more detailed information about nutrient content. 

When selecting a feed, be sure to look for the feed tag or guaranteed analysis. This tag describes the composition of the feed, including protein, fat, fiber, and mineral content. You will also find guidelines for recommended amounts to feed your horse, depending on his weight, workload, and stage of life.

What kind of concentrate does my horse need?

If your horse is not in heavy work and maintains an appropriate body condition score easily, he does not need high levels of concentrate added to a forage diet. A product called a ration balancer is perfect for these horses. Ration balancers are designed for the easy keeper to be relatively low in calories but contain the vitamins and minerals that may be lacking in a forage-only diet. For these horses, daily forage intake at 2% of body weight per day, a ration balancer fed by weight as directed, and access to a mineral block may be all that is needed.

For horses in heavy training, those with a higher metabolism, or those with compromised teeth, more calorie-dense concentrates may be beneficial. For example, a Thoroughbred racehorse will need extra calories from a concentrate to take in enough calories each day for race training, while an aged horse unable to chew adequately will need a forage substitute.

Examples of horses with varying dietary needs



Red, a 16-year-old quarter horse gelding. 

Job: light trail riding 1-2 days per week, easy keeper. Because Red has a less demanding job and maintains his weight well on hay alone, he doesn’t need extra calories from high-energy feeds. A ration balancer is a perfect option to ensure Red has the appropriate vitamin and mineral balance in his diet, without supplying extra calories. 





GiGi, an 11-year-old TB mare

Job: upper-level eventer.  GiGi is a high-level athlete, and as a Thoroughbred, she has a higher metabolism. She is in intense training 4-6 days per week, eats free choice hay, and needs the extra calories from a performance feed to maintain her condition. Many performance feeds offer high-fat content in addition to protein and fiber, as a more calorie-dense option.





Jack, a 25-year-old appendix gelding

Job: retired, hard keeper with many missing teeth. Lack of teeth means that Jack has a hard time chewing hay efficiently, which also puts him at an increased risk of choking. The best feed for Jack is a complete senior feed. The “complete” description means that this feed is formulated to meet all of his nutritional and caloric needs in the absence of hay. Of course, this means that a much higher amount of feed must be fed daily. Regular (non-complete) feeds are generally not safe or nutritionally balanced to feed in such high amounts. If you’re feeding a horse like Jack, remember to check the label of the senior feed to be sure it says ‘complete’.



 Remember, ALWAYS weigh your feed- the label instructions on the bag will have recommendations based on weight (The weight is NOT 1 coffee can…) It is much easier to adjust your horse’s diet when we know exactly how much he is consuming. The easiest way to do this is to put your feed scoop on a food scale, tare it, add feed to desired weight, then draw a line on your scoop so you can feed consistently at every time. Another important note is that feeds are not all the same weight, so if you switch feeds, 2lbs of feed A is probably not the same amount in your scoop as 2 lbs of feed B. As always, if you have questions or would like help selecting a concentrate, consult with your veterinarian.