Miscellaneous Articles

Miscellaneous Articles

The Plight of the Unwanted Horse: Scope of the Problem Help Us Help Horses Euthanasia: Guidance for a difficult decision Euthanasia: The Most Difficult Decision Protecting Your Horse from Disease Outbreaks Panic or Procrastinate? What to Do if Your Horse Has Eaten a Poisonous

Plant AAEP & AHC 'white paper' on the definition of horses as livestock Equine Identification: The State of the Art Wellness Program Is It Possible To Age Horses Accurately? Coggins Test Is He Lame or Is He Neurologic

The Plight of the Unwanted Horse: Scope of the Problem

by Nat T. Messer IV, DVM

For the past 15 years, on average, approximately 1-2% (75-150,000 horses) of the domestic equine population in the United States is sent to slaughter each year 1, with another 10-20,000 US horses being exported to Canada each year for slaughter, and an unknown number of horses being sent to Mexico for that purpose as well (eg: @ 4000 in 2004). In 1998, slightly more than 1% of the domestic equine population was sent to slaughter (approx. 75,000 horses). In comparison, according to the 1998 National Animal Health Monitoring System (NAHMS) Report, 1.3% of horses age 6 months to 20 years (approx 80,500 horses) on all premises surveyed either died or were euthanatized in 1997, while 11.1% of horses greater than 20 years of age (approx. 55,000 horses) on all premises surveyed either died or were euthanatized in 1997.2 Assuming these numbers are at least somewhat representative of what occurs annually, almost 200,000 deceased horses (3-4% of the total equine population) must be disposed of annually, one-third of which are being processed for human consumption, with the remainder being rendered, buried, disposed of in landfills, cremated or “digested”.

“Unwanted horses” represent a subset of horses within the domestic equine population determined by someone to be no longer needed or useful or their owners are no longer interested

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in or capable of providing care for them either physically or financially. Some unwanted horses will find new accommodations; however, most unwanted horses will likely be sent to slaughter with fewer numbers being euthanatized and disposed of through rendering or other means and still fewer simply abandoned and left to die of natural causes. Unwanted horses range from being essentially normal, healthy horses of varying ages and breeds to horses with some type of disability or infirmity, horses that are unattractive, horses that fail to meet their owner’s expectations for their intended use (eg: athletic ability, horses with non-life-threatening diseases, horses that have behavioral problems or horses that are truly mean or dangerous). In many cases, these horses have had multiple owners, have been shipped from one sale barn, stable, or farm to another, and have ultimately been rejected as eligible for any sort of responsible, long-term care.

When the number of unwanted horses mentioned above are combined with the 10,000 or so feral horses being maintained by the Bureau of Land Management (BLM) on privately owned sanctuaries deemed to be un-adoptable or unwanted and 5,000 or so horses being held in short-term holding facilities operated by the BLM awaiting adoption plus some 20,000 or so displaced pregnant mares and their foals from the Pregnant Mare Urine (PMU) industry, one can readily see that the number of truly and/or potentially unwanted horses constitutes a significant number of horses to be dealt with each year and in the future.

To their credit, various equine welfare organizations, breed-specific organizations, and numerous benevolent equine welfare advocates and horse owners have made a conscientious and concerted effort to either provide care for unwanted horses, provide funding for the care of unwanted horses, or to find suitable accommodations for them in both the private and public sector. These efforts, along with widespread efforts to inform the public about the plight of the unwanted horse, and a relatively high demand for horses by prospective buyers presumably accounts for the nearly 80% decrease in the number of horses being sent to slaughter over the past 10 years. The carrying capacity for these retirement farms, rescue farms and sanctuaries, as they are called, is unknown at this point, but despite their noble efforts to provide care for many unwanted horses, the number of unwanted horses far exceeds the resources currently available to accommodate them all. The estimated cost of providing basic care for a horse range from $1800-$2400 per animal per year.3 Even well-meaning volunteers can become overburdened with unwanted horses, at times to the detriment of the horses under their care. Currently, there simply are not enough volunteers, funding or placement opportunities for all of the unwanted horses.

Why are there so many apparently unwanted horses? Is there, as some would suggest, a glut of horses in the United States today? Was there, then, an even larger glut of horses when 200-300,000 horses were being sent to slaughter in the late ‘80’s and early ‘90’s? For the past 5-10 years, the demand for horses on the part of those buying horses has been very good. Over the years, however, this demand has certainly run in cycles that frequently follow other economic trends. In general, when the demand for horses is low, then the number of unwanted horses increases, irregardless of what their bloodlines may be. Recent changes in various breed organizations’ rules, such as permitting the use of embryo transfer and frozen semen, have favored the production of horses, allowing breeders to produce more than one offspring per year from mares, and allowing breeders to more efficiently select for horses with desirable bloodlines or performance records. New technology will further facilitate this practice in the future. Unfortunately, even with the help of technological advances, not every mating will produce a horse that meets the expectations of an owner or buyer. For those in the business of breeding and raising horses, an unsold horse becomes a liability rather than an asset.

Currently, to the author’s knowledge, there is a lack of information about the demographics of unwanted horses other than the generalizations made previously, ie, not marketable, disabled or infirm, unattractive, lacking athletic ability, dangerous or mean. A more detailed study investigating the demographics of horses deemed to be unwanted would allow the horse industry

to focus more appropriately on the problem. For instance, former racehorses are frequently singled out, as examples of unwanted horses when their racing careers end and they are not candidates for breeding or other athletic endeavors. There are undocumented estimates suggesting that less than 10% of the horses that go to slaughter are Thoroughbreds, but just how many of the 80,000 or so horses that went to slaughter last year in the US and Canada were former racehorses? What is the average age and sex of those unwanted horses? What are the types of things that cause them to be unwanted? Are they purebred or grade horses? Answers to questions such as these and many more need to be addressed to be able to understand the problem and potentially reduce the number of unwanted horses.

Whenever there are large numbers of unwanted horses as there are today, there is always concern for the welfare of these horses. According to Rebecca M. Gimenez, PhD, a member of the advisory board of the South Carolina Awareness and Rescue for Equines organization, in a letter to the editor in the April, 2004, issue of a prominent horse magazine4, “we have seen a huge upsurge in abuse and neglect cases over the last three years in our state alone.” She goes on to say, “Looking on the web and talking to veterinarians, farriers, and horse industry professionals all tells me that this isn’t only a South Carolina problem.” Neglect of horses takes many forms and is due to a variety of factors. Could this upsurge in neglect, referred to by Dr. Gimenez, be due to solely to an increasing number of uninformed horse owners unfamiliar with the proper care of horses; or could it be due purely to economic constraints created by the downturn in the economy since 9/11; or could it be due to the availability (or lack thereof) of affordable ways to responsibly dispose of unwanted horses brought about by regulations prohibiting burial of animal carcasses in some locales, costs associated with veterinary euthanasia and disposal by cremation, “digestion” or rendering, or fewer slaughter plants processing horses for human consumption? All of these factors must be considered when faced with this large number of unwanted horses and what should be done with them, always ensuring they are treated humanely and with dignity until the end of their lives

References

1 National Agricultural Statistics Service (NASS), Agricultural Statistics Board, U.S.

Department of Agriculture, 1998 Report. www.usda.gov

2 National Animal Health Monitoring System Equine ’98 Study. Part 1: Baseline Reference of 1998 Equine Health and Management, United States Department of Agriculture/Animal and Plant Health Inspection Service. September 1999. N280.898 www.aphis.usda.gov/vs/ceah/cnahs/nahms/equine/Equine98/eq98pt1.pdf

3 North MS, Bailey D. 14th Annual World Food and Agribusiness Forum, 2004

4 Gimenez RM. Letter to the editor re: unwanted horses. The Horse Magazine 2004; 21(April): 30.

keywords: unwanted horse, . posted: 1/31/2006. Last updated: 1/31/2006.

Help Us Help Horses

by Nathaniel White II, DVM, MS, DACVS

Since its inception in 1994, the American Association of Equine Practitioners (AAEP) Foundation has allocated more than $750,000 to equine research, education, and benevolent programs that have improved the health and welfare of the horse. But the foundation is much more than a funding organization. It’s about collaborating with stakeholders to address the real equine health issues we all care about. By uniting all those dedicated to improving horse health and well-being, the foundation is organizing and delivering relevant research, education, and outreach. The AAEP Foundation fosters the ongoing exchange of information that can make a real difference. Programs include:

Pilot/Emergency Research Funding: More than $350,000 has been awarded to equine research since the Foundation’s inception.

Industry Panels/Summit Sponsor and Host: We are proud to bring the world’s horse health leaders together at meetings and forums for veterinarians to learn and collaborate on the latest research and medical innovations. Our most recent accomplishments include the Equine Genome Panel, Laminitis Blue Ribbon Panel, Equine Respiratory Panel, and the Equine Colic Research Symposium and Panel. Future work of the foundation includes sponsorship of the first Equine Research Summit. This summit will bring together the top researchers, funding agencies, and industry representatives to discuss and prioritize research needs for the horse industry.

Equineresearch.net: Designed to promote and identify current projects through an online catalog of ongoing research studies, this website aims to decrease unnecessary duplication of research and fosters sharing of information between researchers at universities and organizations such as the AAEP Foundation, Morris Animal Foundation, Grayson-Jockey Club Research Foundation, and American Quarter Horse Association Foundation.

Veterinary Student Scholarships: Our expanded scholarship program includes funding graduate researchers, internships, AAEP convention stipends, summer scholarships, externships, and more. We continue to partner annually with the American Live Stock Insurance Company to provide eight scholarships to fourth-year veterinary students. This collaboration has awarded over $350,000 in scholarships to date.

Horse Owner Education Programs: We send horse owners to the AAEP’s Horseman’s Day, an all-day event packed with educational seminars geared to help horse owners improve the health and welfare of their horses. We also assist with various horse owner education efforts throughout the year.

Veterinary Student Education Programs: Throughout each school year, the AAEP Foundation sends AAEP members to veterinary schools to teach students hands-on techniques in dentistry and emergency preparedness, and we assist in hosting farrier-veterinarian short courses.

Providing Equine Emergency and Disaster Relief: In 2005, we created an Equine Disaster Relief Fund, which has raised $100,000 in contributions. We have already allocated $50,000 to help horses through the Louisiana and Mississippi Veterinary Medical Associations in the hurricane-ravaged Gulf region. We also have coordinated supply and feed donations to these regions via our Educational Partners and others within the horse industry.

The AAEP supports the administrative expenses of the foundation, so all donations can be used for programs that help the horse. All horse owners can support the foundation’s goal to improve

horse health by making a donation. Our Equine Memorial Program remains a simple way to donate to the foundation and send a sympathy note in honor of a beloved equine companion or a friend who has experienced the loss of a horse. General donations and planned giving also are options, not to mention the needs of our Equine Disaster Relief Fund. For more information about the AAEP Foundation, see www.aaep.org/foundation.php, contact Amelia Geran at [email protected], or call (859) 233-0147.

keywords: foundation, research . posted: 11/23/2005. Last updated: 11/23/2005.

Euthanasia: Guidance for a difficult decision

by AAEP

Difficult as it may be to contemplate, there may come a time when, for humane or other reasons, you need to consider euthanasia for your horse. Choosing whether, or when, to end a beloved animal’s life may be the hardest decision you ever have to make regarding your horse’s welfare. However, it may be one of the most responsible and compassionate things you can do for your horse.

There is a wide range of circumstances under which euthanasia is a reasonable and responsible choice, and every case is unique. The right choice is clearly the one that is in the best interest of the horse. The American Association of Equine Practitioners (AAEP) recommends that you discuss the following questions with your veterinarian to help you decide what is right for your horse:

1. What is the likelihood of recovery or at least a return to pasture soundness or some level of usefulness?

2. Is the horse suffering?

3. How long will the horse experience the current level of pain or debility?

4. Does the horse continue to show an interest and desire to live, or has it become depressed or despondent?

5. What kind of special care will the horse require, and can you meet its needs?

6. Can you continue to provide for the horse financially?

7. What are your alternatives?

Veterinarians also consider many factors when determining if euthanasia should be considered as an option. The AAEP has developed guidelines to help your veterinarian assist you during this very difficult time. The AAEP’s standards are designed to avoid or end incurable and excessive suffering and apply to all horses, regardless of their monetary value. Among the AAEP’s guidelines for veterinarians are the following test statements:

· Is the condition chronic or incurable?

· Does the immediate condition suggest a hopeless prognosis for life?

· Is the horse a hazard to himself or his handlers?

· Will the horse require continuous medication for the relief of pain for the remainder of its life?

As the horse’s owner, you ultimately have the responsibility for determining your horse’s fate. Your veterinarian can provide you with medical information and help you fully understand the implications for the horse’s future. Your veterinarian can also explain the options and offer comfort and support. But the decision ultimately rests with you, as your veterinarian cannot make this decision for you. If you are in doubt about the prognosis or your options, get a second opinion. It is important for your peace of mind that you feel sure you are making the right decision.

For more information about preparing for and making this difficult decision, ask your equine veterinarian for the euthanasia client education brochure, provided by the AAEP in partnership with Bayer Animal Health, an AAEP Educational Partner. The brochure can also be viewed online at www.myHorseMatters.com, the AAEP’s Web site for all matters relating to horse health.

The American Association of Equine Practitioners, headquartered in Lexington, Ky., was founded in 1954 as a non-profit organization dedicated to the health and welfare of the horse. Currently, AAEP reaches more than 5 million horse owners through its nearly 7,000 members worldwide and is actively involved in ethics issues, practice management, research and continuing education in the equine veterinary profession and horse industry.

posted: 9/30/2003. Last updated: 9/30/2003.

Euthanasia: The Most Difficult Decision

Few things in life are as difficult to accept as death. Death becomes even more painful when you must decide whether to end a beloved animal's life. However, there may come a time when, for humane, medical, economic, or safety reasons, you may need to consider euthanasia for your horse.

The decision to euthanize, or induce a painless death, should never be made without careful consideration. The right choice is clearly the one that is in the best interest of the horse and the humans who care for it.

CONSIDER THE SITUATION

There are a wide range of circumstances under which euthanasia may be considered. Among some of the most common are:

Incurable, progressive disease Incurable, transmissible disease Chronic lameness Inoperable colic

Foals born with serious defects Debilitation in old age Severe traumatic injury Dangerous behavioral traits Undue financial burden of caring for a sick or incapacitated horse Undue suffering for any reason

Every case is unique. Even in similar situations, the decision to euthanize an animal is highly individual. For example, in the case of a severe traumatic injury, such as a broken leg, the animal's psychological makeup can influence the outcome. Some horses may respond better to treatment than others. Some are more cooperative than others, and some have a higher pain tolerance than others. Euthanasia is a highly emotional issue. Yet it is important to address the situation from a practical standpoint as well. Whether you are dealing with an emergency or a long-term illness, discuss the following questions with your veterinarian to help you decide what is right for you and your horse:

What is the likelihood of recovery or at least an acceptable return to usefulness?

Is the horse suffering? Has the horse become depressed or despondent, or does it continue to show

an interest and desire to live? How much discomfort or distress can you accept seeing your own animal

endure? What kind of special care will this animal require, and can you meet its needs? Can you continue to provide for this animal economically? What are the alternatives?

THE VETERINARIAN-CLIENT RELATIONSHIP

As the horse's owner, you ultimately have the responsibility of determining the horse's fate. Your veterinarian can provide you with medical information and help you fully understand the horse's prognosis. Your equine practitioner can also explain the options, and offer comfort and support. But the veterinarian cannot decide for you whether or not to euthanize your horse. If you are in doubt about the prognosis or your options, it is important to get a second opinion.

Equine practitioners are frequently asked, "What would you do if . . ." The question, however, puts your veterinarian in a difficult position. No matter how compassionate and caring, that individual is not attached to the animal as you are, nor will your veterinarian assume the emotional or economic burden of caring for it. Therefore, you must come to a decision that is right for you.

Only in extreme emergencies does a veterinarian act on an animal's behalf without an owner's consent. An example of such a situation might be a horse that gets loose on a roadway and is struck by a car. A veterinarian may notify the local humane society and choose to euthanize a severely injured horse to end its suffering. But such cases are rare.

Remember, too, that a veterinarian must follow his or her conscience. A veterinarian may refuse to euthanize an animal if euthanasia seems unnecessary or unjustified. Or the veterinarian may choose to discontinue treating the animal if an owner is inhumanely allowing an animal to suffer or is unduly prolonging its death.

PLANNING & PREPARATION

If you and your veterinarian agree that euthanasia is the best choice, it is important to prepare as best you can. If you are able to make the decision in advance rather than under emergency conditions, making prior arrangements will ease the process. These guidelines might help:

Determine when and where are most comfortable and practical for you, the veterinarian, and the horse. Keep in mind that removal of the body from the site should be as safe and easy as possible.

If you board your horse, inform the stable manager of the impending situation. Decide whether you wish to be present during the procedure. Only you know

what is right for you. You may wish to ask someone to observe in your absence.

Be aware that, for safety reasons, your veterinarian will probably not allow you to be touching or holding the animal when it is put down.

Discuss the procedure in advance so you know what to expect. Make arrangements for the prompt removal and disposal of the body. Check

with your veterinarian and/or the city or county health departments. Many municipalities have ordinances prohibiting or restricting burial. Removal to a rendering facility or pet crematory may be required.

Explain to members of your family, especially children, in sensitive but honest terms, why the decision was made to euthanize the horse.

Allow yourself to grieve. Finding a support person or group to talk to can help you work through this difficult period.

If the horse is insured, notify the insurance company in advance of the euthanasia so that there are no problems with claims. While the veterinarian will provide you with the required documentation, the notification, filing, and follow-up are your responsibilities.

A PEACEFUL END

As a caring owner, you want your horse to have a peaceful, painless end. Most commonly, the veterinarian will administer barbiturates (sedatives) in a dose sufficient to shut down the horse's central nervous system. The drugs will stop the heart, and the animal will quit breathing, The drugs act quickly and effectively. However, not all horses respond in exactly the same way. If you plan to be present when the lethal injection is given, keep in mind that the horse may simply drop, or could draw a deep breath, shudder, paddle, or show other signs of distress before succumbing.

COPING WITH EMOTIONS

Given the affection we have for horses, dealing with their deaths can be extremely difficult. But death is a part of life, and finding the resources to cope with your emotions is important.

To help you deal with your own grief, there are local and national counseling organizations, including the University of California, Davis, School of Veterinary Medicine's Pet Loss Support Hotline, (916) 752-4200. Your veterinarian may also know of area resources that can help you, so don't be afraid to ask.

INSURANCE CONSIDERATIONS

If your horse is insured, become familiar with the regulations concerning your policy -- even the fine print --before you act. Most insurance carriers require that they be kept fully informed from the beginning about a horse's medical condition, especially if death or euthanasia is a potential outcome. Even in an emergency, a reasonable attempt should be made to notify the insurance company. This notification is the owner's responsibility, not the veterinarian's. If the animal can be stabilized, many policies require a second opinion before a horse is euthanized. However, under extreme circumstances, it is always up to the discretion of the owner and veterinarian to act in the best interest of the horse. By being aware of your policy's guidelines, you can minimize any unpleasant surprises which relate to your claim.

AAEP GUIDELINES

The American Association of Equine Practitioners has developed euthanasia guidelines to help your veterinarian assist you during this very difficult time. The AAEP's standards apply to all horses, regardless of their monetary worth, and are designed "to avoid and terminate incurable and excessive suffering." Included in the guidelines are the following test statements:

Is the condition chronic or incurable? Does the immediate condition suggest a hopeless prognosis for life? Is the horse a hazard to himself or his handlers? Will the horse require continuous medication for the relief of pain for the

remainder of its life?

THINKING AHEAD

Unfortunately, your horse, like all living creatures, is not going to live forever. If your horse remains healthy and happy into old age and dies a peaceful, natural death, you are fortunate. However, by thinking about what you would do in an emergency, or how you would act if your horse's life became painful and unbearable to watch, you can be prepared for whatever happens. And by sharing this plan with others, especially those who care for your horse in your absence, you assume the ultimate responsibility of ownership by easing the decision-making process for everyone. Finally, you show the ultimate respect for your horse by relieving it of unendurable pain or disease.


Protecting Your Horse from Disease Outbreaks

by Dr. James R. "Sonny" Corley

When it comes to protecting your horse from disease outbreaks, Mom was right. An ounce of prevention is definitely the way to go. Infectious diseases can be devastating to your horse and your pocketbook, but there are steps you can take to protect your horse. Prevention is a two-fold process. The first approach is to vaccinate your horse for those diseases for which vaccines are

available. Unfortunately, we have vaccines for fewer than a dozen diseases, so vaccination alone won't provide the total answer.

Should we vaccinate for all of the dozen or so diseases for which vaccines are available? Not necessarily. Select vaccines based on the likelihood of exposure to the disease and by the type of disease produced. Vaccinate first for diseases that are highly fatal and to which your horse may most likely be exposed. These include diseases like tetanus and encephalomyelitis (sleeping sickness). Follow this with vaccination for diseases that are highly contagious even if not highly fatal, especially in horses which are involved in group activities. Vaccination is effective not only in protecting individually vaccinated horses from disease, but also in reducing the overall numbers of infected horses in a group, making exposure less likely for everybody.

The second approach is to prevent exposure to infectious diseases. In order to do this you need to understand how some common infections are transmitted. A number of infectious diseases fall into the "social diseases" category. These are very contagious diseases transmitted by horse-to-horse contact or by sharing intimate items such as water or feed buckets, dose syringes, or the same air space. These include the respiratory viruses such as influenza (flu) and rhinopneumonitis (rhino) and bacterial pathogens such as Streptococcus equi (strangles). While vaccinations are available for a number of these infectious agents, the vaccines are not 100% effective and may not totally prevent a disease outbreak in the face of heavy exposure. The best thing to do is insist that sick horses be isolated and not brought to public gatherings. Meticulous hygiene should be practiced with regard to items in the environment that can transmit the disease. Don't underestimate the value of reducing exposure to infectious agents. Some infectious diseases such as equine infectious anemia (swamp fever) have neither an available vaccination or a cure, so prevention is critical.

While your horse may be at less risk for the "social diseases" if it lives in isolation, even horses which do not come into contact with other horses are not exempt from the possibility of infectious disease. Birds are reservoirs for the virus that causes equine encephalomyelitis, and mosquitoes transmit that disease by feeding on the horse. Tetanus spores are found everywhere in the soil and in the fecal material found wherever horses live. Skunks and other wild mammals infected with rabies may wander into a pasture and bite a curious horse. Opossums are suspected of contaminating the pasture with infective forms of equine protozoal myelitis organisms through their feces. It can be difficult, if not impossible, under certain management conditions to control exposure where horse-to-horse contact is not the primary mode of transmission. This makes it even more important to vaccinate against those agents for which vaccines are available.

As you can see, there is value in employing both strategies when it comes to protecting your horse from disease outbreaks. Be sure to use every resource available. Your veterinarian is an excellent source for information as well as partner for developing a preventative health care plan for your horse.

Dr. James R. "Sonny" Corley is a partner in Acadianor Equine Clinic in LaFayette, Louisiana and a member of the AAEP Public Relations Committee.

American Association of Equine Practitioners4075 Iron Works PikeLexington, KY 40511

(606) 233-0147www.aaep.org


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Panic or Procrastinate? What to Do if Your Horse Has Eaten a Poisonous Plant

Introduction

You provide plenty of good quality feed, water, and turnout--do you still have to worry about your horse's getting sick from eating a poisonous plant? While common sense and good horse management are your horse's best protection, toxicology, like most other life sciences, has many unanswered questions. But by taking advantage of what is known, you can decrease the chance of your horse eating the wrong plant at the wrong time.

Since most poisonous plants do not taste very good, often horses will need a reason to eat them. The most common reason is simply hunger--the horse isn't getting enough to eat or the nutritional quality of the diet is poor. Owners also can unintentionally feed toxins to their horses through contaminated hay and grain or by offering certain tree and bush clippings. Just a few leaves from the Japanese yew, a common lawn ornamental, can kill a horse within hours. Leaves from maple trees also can be fatal.

Allowing horses to graze a pasture after it has been sprayed with a herbicide, but before the weeds have died and disappeared, is another commonly overlooked reason a horse might become poisoned. Phenoxy compounds such as 2,4 D are believed to make the plants taste better and, in some cases, to increase concentrations of natural plant toxins.

Treatment

The first thing to do if you suspect your horse has ingested a poisonous plant is to prevent further exposure. Depending on the source, this might mean removing your horse from the pasture and putting it into a stall or removing all hay, grain, and bedding from an already stalled horse. Contact your veterinarian immediately. While waiting, attempt to determine how much was eaten and what was eaten (see the References section at the end of this article for tips on plant identification). Small amounts of some toxins can be fatal in a very short time while others require large amounts to be eaten over weeks or months.

Pyrrolizidine alkaloids can act in both ways, causing unthriftiness over months or blindness and staggers leading to death in just a few days. In general, however, toxicity depends on several factors: the soil, climate, and growth stage of the plant; the horse's age, weight, and individual tolerance; plus how much other feed was in the stomach when the toxin was consumed.

Some poisonous plants have specific antidotes, but for most toxic plants, the effects can only be treated symptomatically. This means supportive care and measures to limit further exposure until the crisis has passed. Depending on the specific toxin (even if the horse survives), there can be permanent signs of disease. For example, horses which have eaten enough locoweed over time to show central nervous system signs, such as incoordination, might never be safe to ride. Locoweed also is an example of a poisonous plant that horses might seek out to eat once they have had some because it could be addictive.

Since there are many different kinds of poisonous plants, there are many different signs of poisoning. The most common signs of toxin ingestion include the following: difficulty swallowing

or breathing, colic, founder, hyperexcitability/seizures/incoordination, limb edema or photosensitivity, and even collapse and sudden death. Often these syndromes must be differentiated from similar diseases caused by infectious, nutritional, or age-induced problems by a thorough case history, physical examination, and diagnostic workup. Owners should not attempt to treat poisoning themselves but should contact their veterinarian immediately, which could mean the difference between life and death.

Prevention

Rather than treat a horse which already has begun to show signs of eating a poisonous plant, owners should strive to prevent their horses from ingesting the plants in the first place. Know the common poisonous plants in your region of the country, including the time of year they are the most palatable or the most toxic. For example, white snakeroot poisoning usually only occurs during midsummer to early winter when the pasture has become eaten down or dried up. Limiting pasture time during those parts of the year and making sure the horse is well fed before being turned out reduce but do not eliminate the risk. Also, do not overstock pastures with too many horses per acre, and maintain pastures accordingly.

Provide the best quality hay and grain possible, checking each flake of hay and scoop of grain carefully before feeding it. Hay should be green and smell pleasant. Grain should not have any corn fines or screenings, since these often contain the compound that causes equine leukoencephalomalacia, commonly known as moldy corn poisoning. If you have any doubts about the quality of your feed, ask your veterinarian to send in random samples for testing; even corn that looks fine can be fatal. You could even organize a "pasture walk" for your local riding club led by an expert who can point out poisonous plants.

References

It's a good idea to know to whom you should turn before you find yourself in an emergency situation. For poisonous plant identification, start with your local veterinarian, who can put you in touch with your county extension agent and the nearest university. Greenhouses, herbariums, florists, and botanists can be other sources of expert information. Weed experts usually need the entire plant (including the roots) in order to identify it. For immediate identification, wrapping the plant in moist paper will suffice. However, if the plant needs to be mailed somewhere, pressing it dry between papers is best.

Several resources were used in preparing this article. For a list of references, see The Horse Interactive at www.thehorse.com/0998/toxicplants.html or ask for books at your local library.


(606) 233-0147www.aaep.org



http://www.thehorse.com/0998/toxicplants.html

AAEP & AHC 'white paper' on the definition of horses as livestock

What is livestock?

Livestock is most commonly considered animals kept or raised in a farm or ranch setting and used in a commercial enterprise. The raising of livestock is an agricultural endeavor that promotes the preservation of green space and a way of life that many in today's society desire.

Are horses livestock?

Yes, horses are livestock. Traditionally, and legally, horses have been considered livestock in the United States. Even today, horses are still kept and raised on a farm or ranch and are used in a commercial enterprise. The United States horse industry is a major business that makes a significant contribution to the economic well-being of the entire country. The U. S. horse industry has a $112.1 billion impact on the U. S. economy; generates 1,404,400 full-time equivalent jobs; and pays $1.9 billion in taxes to all levels of government.

What effects might changing the legal status of horses have on the industry?

State and federal support and moneys. The care and regulation of horses and horse related activities come under the purview of the United States Department of Agriculture on the national level. In most states, the state department of agriculture is charged with the regulation of horse related activities on the state level. Part of the responsibility of the USDA is to improve and maintain farm income; develop and expand markets abroad for agricultural products; protect the soil, water, forests, and other agricultural products; and carry out agricultural research.

The USDA provides valuable technical expertise and monetary support for such things as research into the prevention of equine diseases such as Equine Viral Arteritis (EVA), Vesicular Stomatitis Virus (VSV), Venezuelan Equine Encephalomyelitis (VEE), and Contagious Equine Metritis (CEM); the enforcement of the Horse Protection Act; and development and enforcement of the Safe Commercial Transportation of Equine to Slaughter Act. Many state departments of agriculture are also providing valuable assistance to the horse industry through research and regulatory programs. If livestock status is taken away from horses, there is a possibility of losing the already limited financial support equines receive from the USDA for research, regulation, and disaster relief.

Humane laws. All 50 states have animal anti-cruelty laws. Some of these laws are written specifically for livestock and others are written specifically for non-livestock. Livestock anti-cruelty laws are usually written to ensure the humane treatment and care these animals deserve, while still providing for the use of the animal. If horses are legally considered non-livestock, livestock anti-cruelty laws will no longer apply.

Limited liability laws. Many states are now passing what are commonly referred to as "limited liability laws." One of the purposes of these state laws is to provide stable owners, equine event organizers, and trail ride organizers protection from lawsuits that may arise if an individual is injured while attending or participating in such an event. Those involved in the horse industry realize the horse is a potentially dangerous animal, and are aware of the risks when dealing with them. However, many of these state laws are not limited only to horses; they encompass all

livestock or farm animals. If horses are no longer considered livestock, a law which so many horse people worked to pass might no longer protect them.

Tax issues. Currently, under federal tax law, commercial horse owners and breeders are treated as farmers. This has certain tax ramifications which could be changed if horses were not considered livestock. In addition, horse owners and breeders are treated differently by state excise and sales taxes because horses are considered livestock. These advantages could be lost. If horses were no longer livestock, horse breeding would no longer be an agricultural endeavor and federal and state taxes for horse operations could increase.

Why do some want to change the definition of horses?

Human consumption. Some individuals wish to change the definition of horses from livestock to something different because they believe it would prevent the use of horses for human consumption.

The decision to send a horse to a processing facility where it will be slaughtered, like other livestock, for human consumption is a personal one that should not be mandated by law. This is one way of disposing of horses that cannot be taken care of or that no longer have any viable use. Taking this option away from individuals could make conditions worse for some horses. If a horse cannot be sold at a sale because it may go to a processing facility, it might become a candidate for abuse.

The disposal of a horse's carcass is also a concern. In most cases, county or state laws make it illegal simply to bury a horse on your property or dump the carcass in a landfill due to human health concerns. To some, the cost of disposal for horses might be so high that they are simply left to stand in a field until their death. The instantaneous death at a federally inspected and regulated processing facility is more humane than a slow, lingering death from starvation. These facilities must comply with strict federal and state codes designed for the care of these horses. These codes govern euthanasia, as well as the methods used, and provide for the safety of the meat produced.

The horse has long been considered livestock in the United States and throughout the world. This does not prevent individuals from enjoying their horses as companion animals. That is their privilege, just as it is the right of others to continue to care for them as livestock. Changing the legal definition of horses to companion animals under state law, however, could adversely affect horse owners and breeders and not necessarily better protect horses. Horse owners and others should be mindful of this when considering various state initiatives.


(606) 233-0147www.aaep.org



Equine Identification: The State of the Art

by Tim Cordes, DVM

Tim Cordes, DVM

INTRODUCTION

Since the dawn of civilization, human beings have sought ways to identify the animals they own in order to distinguish them from animals owned by others. In the United States, early equine identification was a description or sketch of the animal. Hot iron branding, introduced by Spanish settlers in the early 1800s, was adopted chiefly by ranchers in the western states. Lip tattooing came into use in the late 1800s—first in the U.S. Army, replacing the hot iron brand, and later in the tattooing of racehorses.

Reliable horse identification becomes especially critical in emergency situations. Lessons from Hurricane Andrew demonstrate that lack of permanent identification leads to theft and confusion over ownership as horses stray, are evacuated, or otherwise separated from their owners. Horse identification is also important during outbreaks of serious infectious disease, as officials try to find out which horses traveled where as well as to identify horses that may have been exposed to disease.

The need for permanent, easily proven equine identification is a basic one throughout the equine industry. Yet the standard methods of horse identification and associated recordkeeping currently in use are too often too basic and too disjointed. Electronic identification and biometric methods of identification are the newest and most promising methods of equine recognition and recordkeeping.

ELECTRONIC IDENTIFICATION OF EQUINE

Electronic identification (EID) of horses and other animals uses implantable transponders (microchips) which are activated by a radio frequency reader. These readers are used to identify and display a transponder’s letter and number code, which can then be traced back to the owner. The passive role of the microchip gives it durability throughout the life of the horse.

Field trials in horses between 1985 and 1990 revealed that transponders, typically the size of a grain of rice, were easy to implant with a 12-gauge needle. The trials also demonstrated that their

glass covering could be implanted safely in horse tissues with little or no tissue irritation. Initial problems of transponder movement within tissue were solved by adding a special cap to the transponder.

Transponders are implanted into a ligament in the left side of the horse’s neck, which is the U.S. Department of Agriculture/Food and Drug Administration-approved implant site for all equine in the United States. The International Standards Organization (ISO) has established a unifying standard for equipment produced by all major electronic identification manufacturers and radio frequency reader manufacturers. A universal reader is available and has been introduced into the marketplace. It is expected that such readers will be more broadly available in the near future. All scanners will need to meet ISO standards.

In the United States, the State of Louisiana’s Equine Infectious Anemia (EIA) Control Program provides a good example of the successful use of implantable transponders. Electronic ID as a form of permanent identification has been found to be very practical and is given much of the credit for the reduction of EIA in Louisiana. To date, implantation has occurred in approximately 100,000 equines in the state.

Implantable transponders are an impartial method of equine identification that can be used in concert with natural markings, age, gender, breed, and hair coat color as well as any existing human-made brands, marks and scars. With the rapid growth of technology, the role of computers in business and veterinary practice has become very important. Implantable transponders are a practical and computer-compatible method of identifying horses and other animals.

BIOMETRIC METHODS OF EQUINE IDENTIFICATION

Biometric identification technology involves the "measurement" of a biologic feature in order to accurately differentiate one animal (or person) from another. In human technology, common applications currently include retinal scans, iris scans and scans of facial characteristics.

With respect to horse identification, retinal scans currently are probably not possible because of the difficulty of obtaining an image of a horse’s retina. Iris scans, however, are expected to be very useful. Iris scans use common digital technology (like a digital camera) for input into and analysis by a computer program. The resulting output, termed an "iris code," contains approximately 512 bytes of data. An iris code can be stored in a database and used for later identification of a horse. The technology has been determined to be quite accurate in humans and is being used commercially for a variety of security purposes, including computer login control.

Necessary equipment includes a digital camera for iris image gathering, a PCI card frame grabber to transport the digital image from the camera to the computer and a special processing

card for computer analysis of the iris image. The remaining computer system provides data management and storage.

The probability of two human irises producing exactly the same iris code is 1 in 1076 power. The process of identifying an iris using a large database of iris codes requires only 1-2 seconds. These are strengths of the identification system. A weakness is the fact that, currently, the digital camera needs to be 2-3 inches from the iris. However, various optic arrangements may increase this distance, thereby increasing the horse’s comfort and cooperation.

The electronic method of identifying horses is simple to use and has been shown to be successful in terms of disease control and establishment of ownership, especially with wider use of the universal scanner. The biometric method of horse identification appears to be extremely reliable, and, while more difficult to use, should be able to provide more information quickly about a particular animal through the use of a searchable database.


Wellness Program

by Gregory C. Smith, DVM

Is Your Horse Enrolled in a Wellness Program?A wellness program for your horse will save you time, money and, most of all, the headache of worrying if you’re doing the right things at the right time. But with all the sources of horse health care information available today, how do you decide what’s right for your horse? Books, magazines, the internet, your farrier, the feed store operator and other resources can make you unsure of what practical horse care is anymore.

Fortunately, you probably already know someone who has the education and experience to sift through the latest information in horse health care, coordinate with the other professionals involved in the upkeep of your horse, and develop a customized health plan just for you: your equine veterinarian.

A wellness program for horses is not a new idea, but new ideas are what make them so beneficial. The veterinary community is among the first in the industry to learn about advancements in health care as well as disease outbreaks, product complaints and other information that may affect how you care for your horse. By developing a closer working relationship with your equine practitioner, you take advantage of this “inside scoop” as the two of you work together to design a comprehensive health care plan for your horse.

A wellness program should have vaccinations, dewormers, dentistry and nutritional consultation as the cornerstone procedures. While that sounds simple and obvious, there is much controversy and change in each of these basic areas.

For example, veterinarians not too long ago were recommending that even foals from vaccinated mares begin receiving their own vaccinations within the first few months of birth. On-going research has shown that antibodies from the mare’s milk for some diseases (such as influenza) last much longer than originally thought. Therefore, the foal’s first vaccinations can be given much later (at eight or nine months of age for influenza if the mare was vaccinated). Other research has produced a new vaccine combining influenza and rhinopneumonitis which can be given either through the intramuscular or intranasal routes.

With the introduction of more effective dewormers, it is even more critical to plan for parasite control. Issues such as resistance, whether to use a daily dewormer or a purge dewormer, and the increasing importance of encysted small strongyles need to be considered as you and your veterinarian select products, schedule fecal examinations, and set up environmental control measures.

Dentistry in the horse has been transformed in the last decade or so to a science that helps keep your horse in good weight and good performance. This has become especially important as horses are living longer and longer. The days of hand-floating every horse in the barn on one visit have given way to oral examinations and scheduling preventive and corrective dental procedures appropriate for your horse’s age and use.

Even if your horse is at his ideal weight for what you’re doing with him, there’s still a benefit to showing your veterinarian what and how you’re feeding your horse. Not only will you have the opportunity to ask questions about nutrition and other topics during a tour of the feed shed and pasture, but you may also end up reducing the number of supplements you give your horse, thereby reducing your feed costs.

While all wellness programs also include a basic physical examination in addition to the services above, some veterinarians include other procedures and consultations with their packages based on the needs of the individual owner and horse. Many veterinarians will alert you to the need for a visit or for a product to be administered, relieving you of detailed record-keeping. Most importantly, you can help keep the information highway from becoming bumper-to-bumper with confusion by developing a partnership with your local equine veterinarian.

Dr. Gregory C. Smith, owner of East County Large Animal Practice in El Cajon, California, a three-doctor Practice of Excellence as awarded by Veterinary Economics magazine, with Dr. Lydia F. Miller, AAEP Owner Education Consultant

1) title Is Your Horse Enrolled in a Wellness Program?2) author Gregory C. Smith3) Title DVM4) Source Forum5) Date March 20016) Menu category Parasites Vaccination Veterinarian-Client Relations


Is It Possible To Age Horses Accurately?

by M.T. Martin, W.L. Scrutchfield, J.R. Joyce, Matthew Martin

Aging horses by their incisor teeth is as much as art as a science. Traditional "indicators of age" such as eruption date, "cups," Galvayne's groove, hooks, shape of the table surface of the lower central incisors, etc. often result in wide age estimates. The authors believe that accuracy can be improved by first placing horses less than 20 years old into one of four age groups before applying the traditional indicator. Then by using a systematic approach and applying the following concepts, the age of most horses can be accurately estimated.

Important Concepts:

1. Horses under 20 are placed into one of four age groups by examining a single tooth, the upper corner incisor (UCI).

2. All traditional "indicators of age" can be used but eruption dates, "cups," Galvayne's groove and the table surface shape of the lower central incisors are most reliable.

3. When examining horses under five years the examiners should be aware that time of year is very important. For example, a three year old’s teeth will look much different in February than they will in November.

4. Most horses are born in the spring and all have a birthday on January 1.

5. "Atypical" horses do occur and can usually be recognized when their age group and indicators do not match, resulting in wide age range estimates.

Age Categories:

Under five - This age group has a deciduous (baby) UCI from 8 months to 4 _ years. Eruption time of the central, middle and corner incisors (2 _, 3 _, 4 _ years) are the primary source of information in this age group and are considered highly accurate in the general population.

Five to nine - UCI is now a permanent tooth and should be wider than it is tall (5-6 years) progressing toward square (9-10 years). Younger horses in this age group should have "cups" on the table surface of the lower incisors. These cups will be gone from the central incisors once the horse turns six years old, gone from the middle incisors by age seven and gone from the corner incisors at the age of eight or nine. The table surface of the lower central incisor should be oval from side-to-side in this age group.

Ten to fourteen - The UCI should be square (9-10 years) to taller than wide (12-14 years). Galvayne's groove should start to appear at the gum line when the horse is 10 years old and progress to halfway down the UCI by the age of 15. The table surface of the lower central incisor should be round to triangular.

Fifteen to twenty - UCI should definitely taller than wide thus the saying "long in the tooth." Galvayne's groove will usually be halfway (15 years) to all the way down the UCI (19-20 years). The central incisors are significantly smaller than the middle incisors and the lower central incisor table surface should be oval from front to back.

As horse's approach the age of 20, the accuracy of estimating their age decreases. Breed differences can also occur. The best advice when learning to age horses is to look at horses of known age within a breed and use a systematic approach such as the one described above.

Authors M.T. Martin and W.L. Scrutchfield are Equine Field Service Clinicians and J.R. Joyce is a Community Practice Clinician at Texas A&M University. Matthew Martin is an undergrad in Ag. Business at Texas A&M University.


Coggins Test

by Charles J. Issel, DVM, PhD

My horse was turned away from a horse show because we didn't have a current negative Coggins test. Is it really that important?

To answer the question directly, you were turned away because it is customary to monitor the serum of horses for antibodies to equine infectious anemia virus (EIAV)--and we use testing to prevent the movement of virus carriers and spread of the infection caused by that lentivirus (a virus that can cause slowly progressive, often fatal animal diseases).

The Coggins test is the most commonly used means of finding antibody to EIAV, which causes a persistent infection in horses. There also are three rapid ELISA tests for EIA. ELISA test results can be obtained within an hour. A Coggins test result requires at least 24 hours. Testing for EIA has been done for more than 25 years to identify virus carriers and to regulate their movement. There are no treatments or vaccines for this lentivirus relative of HIV in humans. (For more information on EIA, see The Horse of August 1999.) Since there is no cure for the infection, currently the only options for control of the spread of the infection are permanent quarantine of test-positive horses, or euthanasia.

The potential for spreading EIA is highest at congregation points like horse shows, when horses are in close contact. Transmission is generally effected by transfer of blood between horses through the interrupted feeding of insects, e.g., horse flies. To stop the spread of the infection and disease, one must know the status of each individual and control movement of test-positive animals. The highest-risk scenario is a congregation point (such as a horse show, trail ride, or other competition) that does not require a negative test for EIA.

Actually, a negative test result for EIA is only accurate the day the blood is taken. If our horse is test-negative and all its contacts have been, are, and will be test-negative (as are all their contacts), we can rest assured that our horse will remain test-negative. Therein lies the rub. Testing of 100% of our contacts is virtually impossible.

http://www.thehorse.com/9908/eia9908.html

In Utah, infections with EIA have been found in feral, free-roaming horses. Routine testing for EIA of domesticated horses at risk has not occurred in that area historically. When domestic and wild horses intermingle, there is risk of EIA infection either being introduced by the domesticated horses into the wild population, or the other way around. Most likely both circumstances could occur.

The greatest risk of acquiring EIA today in the United States is from the "untested reservoir" population. While some states have annual testing, no one has been successful in testing 100% of the horses in their jurisdiction. To test every equid would allow us to eradicate EIA from the population. Each state has its own set of regulations to monitor EIA. In some areas, testing has been done on a regular basis over a long period of time, with very few positive cases found in recent years. This is the case in the northeast, for example, from Maine to Maryland, where an average of two horses out of nearly 200,000 tested each year has been positive. Evidence of a negative test for EIA is required to move a horse on a public road in the state of New York--regulations such as these have thwarted the spread of the infection and disease.

I recommend that all horses considered for purchase have evidence of a recent negative test for EIA. If there are questions about the status of all the previous contacts of the horse, we recommend the sale be contingent on a second negative test about 45 days after the transfer.

One idea to help increase testing for and awareness of EIA is for the states to grant a "reward" to owners who remove test-positives from their herds.

Charles J. Issel, DVM, PhD, is the Wright-Markey Professor of Equine Infectious Diseases at the Gluck Equine Research Center, University of Kentucky.


Is He Lame or Is He Neurologic

by B.D. Grant, DVM, MS, ACVS, J.H. Cannon, DVM, ABVP

B.D. Grant, DVM, MS, ACVS, J.H. Cannon, DVM, ABVP, San Luis Rey Equine Hospital, Bonsall, CA

"Your horse may be a Wobbler" is a statement made by the attending veterinarian that very few horse owners want to hear. A "Wobbler" diagnosis produces the same fear of the unknown that the dreaded diseases "colic", "founder" and "laminitis" are capable of producing. This article is designed to help the reader have an improved understanding of the clinical signs, diagnostic tests and possible successful treatment and prevention of the "Wobbler" syndrome.

A "Wobbler" is a horse with a damaged spinal cord. The most obvious clinical sign is an abnormal gait characterized by wobbling, or a horse that looks like he has had a fair amount of tranquilizers. Severe damage can actually result in a horse that may fall and have difficulty getting up. Mild cases may only present an inability to change leads, stop smoothly or a negative change

in behavior that results in poor performance. The mild cases are often confused with subtle problems of the hind legs, especially of the hock and stifle. The hind limbs are affected because the nerves which supply the area are located on the outside of the spinal cord in the cervical (neck) area, therefore, are more easily damaged than nerves leading to the front limbs protected deep within the spinal cord.

The major causes of spinal cord damage include malformation of the cervical vertebra, trauma to the vertebra from falling and viral (herpes or rhinopneumonitis) and protozoa (Sarcocystis neurona) infections. The clinical signs of each of these problems can be very similar as each one can damage the spinal cord in the neck region.

In order to provide accurate information for the treatment and long-term prognosis, it is necessary to obtain a complete diagnosis as soon as possible. Arriving at a clinical diagnosis usually requires combining the information from a complete neurological exam, radiographs of the skull and cervical area, a myelogram and testing the spinal fluid.

A neurological exam can be performed by your veterinarian or by an experienced horse person. The tests are not complicated, but the interpretation of the results does require some experience and good observation. We recommend that the exams be videotaped so other examiners can render an opinion without having to travel. The tapes can also serve as a reference to determine if there is any clinical improvement with treatment. The following are some of the more basic tests and what is normal and abnormal about each.

1. Back withdrawal: Pressure is placed over the back and pelvis to determine if the patient resents the pressure. A normal horse will not react but a "Wobbler" will withdraw by depressing the spine in a squatting position. This is not a sign of pain but a sign of weakness as a result of nerve damage. Horses with painful spines do not usually squat because squatting would result in more pain.

2. Tail and anal tone: The normal horse should have tone in the tail when it is elevated. A horse with spinal cord problems will have a very flaccid tail especially if the damage is in the lumbar or sacral areas. The anus should pucker when stimulated and not remain wide open.

3. Panniculus or skin sensation: The sensation along the entire spine is tested with the end of a ballpoint pen on both the left and right sides. A normal horse should move the skin and muscles as though irritated by a fly. Horses with spinal problems often do not react as though they were going to have an injection.

4. Mobility of the neck: The horse is quietly and gently encouraged to bend their neck so that the nostrils reach behind the shoulder. This should be repeated on both sides. The use of a carrot or a handful of grain will often encourage the patient to reach their neck back behind their shoulder. A horse with a painful neck, cervical fracture or an arthritic vertebra will refuse to bend the neck or will try to twist around to the carrot by moving their legs. Some horses with severe problems will become more ataxic (drunken) after this test. Others may have a difficult time eating either off of the ground or from an elevated hay net.

5. Placement tests: The front legs are taken one at a time and crossed over the front of the other leg or placed in a wide stance. Normal horses should instantly replace their legs to the proper position while horses with spinal cord problems can take a long time to recognize their awkward stance. The test should be repeated on the opposite side and can also be done on the hind legs on subtle cases. We do not recommend doing this on very obvious "Wobblers" as there is some risk to the patient, handler and examiner when trying to perform this on horses with very poor balance.

6. Tail sway: The tail is pulled to each side by the examiner while an experienced handler is walking the patient. Normal horses resent the tail pull, but "wobblers" are easily pulled to the side while walking and when the pressure is released, they overcorrect or sway to the side.

7. Tight circles: The patient is walked in a very tight circle pattern. A normal horse has the outside front foot placed in the front of the inside front foot and the inside hind foot placed in front of the outside hind foot. Horses with spinal cord problems will be confused and often reverse this order or pivot on the inside foot instead of lifting the leg. They will also swing the hind leg very wide (circumduction). Severe cases may step on themselves or almost trip and fall.

8. Hills: The patient is led up and down an incline with the head in a normal position and then again with the head elevated. Normal horses place their hind feet flat on the ground and do not elevate the front feet (hypermetria) when going down hill. When coming up hill, the normal horse should also walk with flat rear feet. Abnormal horses walk downhill as though they have been tranquilized (truncal ataxia) and will knuckle over on the hind fetlocks. The patient will walk on their toes coming up the hill and swivel the toes and hocks laterally trying to get enough strength to get up the hill. Walk the patient with the head elevated and if the horse is affected, the signs should be even easier to see.

9. Free exercise: If the patient is not severely affected then they are allowed to run free in a paddock. Horses with spinal cord abnormalities bunny hop with the hind legs at a canter, will often be on the incorrect lead behind, and will knuckle over behind when trying to stop. Mildly affected horses have a very impressive animated gait at the trot that usually makes dressage owners salivate.

10. Hopping: an experienced examiner on soft footing should only do this test. Affected horses will almost fall if encouraged to hop with one leg held off the ground. Some horses will have a strong side and a weak side. If the horse hops when the left front leg is off the ground and refuses to hop when the right leg is off the ground, we assume that the left side is affected.

11. Blindfold: an experienced examiner on soft footing should only do this test. We do not usually do this test because it does not work on horses that only have spinal cord problems. If the horse has a brain or middle ear problem, they will fall down or start to lean.

After the neurological exam is complete and there is a high index of suspicion that the cervical area may be the source of all the problems, a series of radiographs (x-rays) are taken with the patient lightly sedated. The radiographs are then examined for fractures, collapsed intervertebral disc place, misalignments, narrowed spinal canal measurements and arthritic articular facets. Depending on the findings and the relative urgency, a myelogram is the next procedure indicated.

Myelogram

A myelogram is obtained under general anesthesia by replacing the clear radiolucent cerebrospinal fluid (CSF) with an iodine base fluid that will outline the spinal cord when viewed by radiographs. This is accomplished by carefully inserting a 3" spinal needle into the space between the first and second cervical vertebra (A-O space). Feeling a "pop" indicates penetration of the protective membrane (dura mater). The CSF is withdrawn through a long extension tube with dye being injected over a three-minute period. A series of radiographs are then taken with the cervical vertebra in neutral, flexed and extended positions. Cord compression is diagnosed when both the dorsal and ventral dye columns are 50% reduced in width when compared to the neutral position.

Many times, more than one area is compressed, which is very important to know when the different options for treatment are being considered. Other important things to know before

considering a myelogram, is that it is an invasive procedure done under general anesthesia on horses that do not have a normal balance and that these factors can lead to a small percentage of horses having complications (<5%) during recovery. The quality of recovery from anesthesia is important especially if surgery is being considered. If the patient has a quiet recovery from the myelogram anesthesia, recovery from surgery will generally go well.

Laboratory Tests

The analysis of the CSF is usually done during the time of the myelogram. The fluid is examined for increased white blood cells that may indicate infection, for unusual cells that may be seen with a neoplastic (cancer) condition and for the presence of antibodies for herpes virus or protozoa (sarcocystis). There are also some families of horses and environmental areas that result in Vitamin E deficiencies and blood samples for Vitamin E levels can also be sent off to laboratories that specialize in these conditions.

Bone Scan

The use of a radioisotope (technetium 99) to detect areas of bone inflammation in the spine is routinely done at the hospital. The isotope is injected into the vein and after three hours, the horse is put in front of a detector. With the magic of computers, an image is created of the area being scanned. If the bone in that area is inflamed, there will be an increased amount of isotope at that site, which is manifested by a more intense image.

After the neurological exam has been completed and neurological abnormalities have been seen, there are a number of tests that can be done to determine the cause of the damage to the spinal cord. Without an accurate diagnosis, it is difficult to discuss possible treatments and the long-term results.


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