Tetanus is caused by a bacteria, Clostridium tetani. The toxin (poison) produced by the bacteria acts on the junction between muscles and nerves in the body, causing them to contract.. Like a stuck gas pedal, the muscles cannot relax and the typical signs seen are stiffness, spasms, and then convulsions. Spasms of the muscles which are used to chew cause this disease to be nicknamed lockjaw. Other signs seen are erect ears, raised tail, and the legs will often assume a ‘sawhorse’ appearance due to the contraction of the leg muscles. Horses will frequently sweat profusely and this can be confused with colic. Death will follows in about 80% of animals affected.
C. tetani is found in the soil and in the intestines of some animals. It becomes a problem when it gets into tissue that is dying or necrotic. Tetanus is unable to grow in normal tissue because of the high oxygen level in normal tissues. So wounds that are deep and dirty or not cared for properly are the prime targets. The bacteria usually take about 2 weeks to make enough toxin to cause disease.
Horses are, next to man, the most susceptible to tetanus. The vaccination for tetanus is called a “toxoid” and is made up of killed bacteria. The body recognizes the toxin as foreign and can form antibodies to it. Antibodies are specific to each type of molecule and attach to the toxin rendering it inactive. The body then ‘remembers’ the toxin so that it can act quicker when the animal is exposed. Exposure to the disease also vaccinates the animal but they usually die before they can mount a sufficient response to cure themselves. The vaccine is given yearly and is usually in a ‘ 4 way’ or ‘5 way’ with other vaccines. If your animal has a deep puncture wound, and has been vaccinated previously, a booster shot should be given. The booster is available from your vet or most equine supply houses. If your horse has not been vaccinated previously and is exposed, an antitoxin ( pre-made antibodies) is given with the toxoid to protect your horse while the vaccine starts to work. By the way, cats seem to be the most immune to this disease and dogs are very much resistant. This is why we do not vaccinate cats and dogs for it. Cattle, sheep and goats are susceptible to the disease and get their own vaccine.
The Rocky Mountains have seen less Tetanus then many other parts of the world. However, since the vaccine is cheap and the disease is deadly, it is prudent to vaccinate and care for all wounds by flushing them out with an iodine solution (Betadine, Povodine). Vaccination (around $5 at Country General) of foals begins at 3 months and boosters are yearly. Treatment of Tetanus is mostly keeping the horse from hurting itself by sedating it, and treating the infection with antibiotics and antitoxin. Tetanus is easily treated with penicillin but the effects of the toxin can last for weeks.
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The term "strangles" is a common one in the horse world, but not always completely understood. A quick look at what this disease is and whether your horse can get it are probably in order. "Strangles" is a more common term for what is a bacterial infection in the upper airway of horses. The bacteria is known as Streptococcus equi. Horses can pick up Strep. equi by inhalation into the nasal chamber and the upper throat. The infection settles in the lymph nodes of the jaw and upper throat and these lymph nodes begin to enlarge as a result and form abscesses. The disease gets it's sinister name because, as these lymph nodes get bigger, they commonly compress the airway and hinder the horse's ability to breath.
Clinical signs are seen in young horses, usually 6 months to 2 years of age, although adults can become infected. "Strangles" commonly begins as a fever, decreased appetite, lethargy, and a runny nose. With progression of the disease, the throat region will become swollen and the horse may extend its neck slightly to breathe and eat more easily. In the most severe situations, horses left untreated can die as a result of "strangles" from an inability to breath or from spread of the infection to other parts of the body. In less severe cases, the lymph node abscesses will rupture either to the outside spreading bacteria in the environment or into the horse's throat region; and, occasionally, they will regress.
"Strangles" is very contagious and is spread from horse to horse by direct contact with animals shedding the bacteria. The bacteria are present in nasal secretions and in the content of ruptured lymph node abscesses. Keep in mind that horses shedding the infection may not look outwardly sick. The bacteria can also be picked up from surfaces that have been contaminated by a shedding horse, such as fence posts or water buckets or feed troughs. This potentially serious condition can be treated. Ask your veterinarian about the treatment of "strangles", how to help protect your horse, and what to do in the face of an outbreak among a group of horses.
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Pigeon Fever is not the latest dance craze, its a disease of late summer and early winter in horses and cattle. Also called ‘Dry Land Distemper’ and ‘Ulcerative Lymphangitis’, it is caused by the organism Corynebacteria pseudotuberculosis. This is the same organism which causes Caseous Lymphadenitis in sheep and goats. In all species the disease is thought to be harbored in contaminated soil and equipment (tack, clippers, etc.) and infection is usually through the action of insects or any contact of contaminated items with broken skin. In horses, the disease classically presents as a cellulitis (swelling) of the pectoral (breast) area and forelegs. I have also seen this disease as a swelling of the abdomen and hind legs. The limb swelling is due to lymph node blockage which prevents the exit of fluid from the legs. The abscesses progress to open wounds and produce a yellowish-green discharge. This discharge is full of bacteria which can last for months on hay, soil or equipment. In cattle there may be many small to large wounds on the legs and undersides. There is often a fever present. By the way, cattle normal temperature is 101 degrees F and horses are around 100 degrees F. Sheep and goats can get a chronic wasting syndrome when the abscesses form in the lungs or abdominal organs. In horses the disease can be fatal if the abscesses spread to the abdomen.
Treatment usually consists of hot-packing the swollen areas until the abscess matures (fills with pus) and then lancing the abscess to drain the discharge and flushing with an iodine solution. Antibiotics are not usually effective against the organism because of the nature of the swelling and usually only tend to delay the maturation of the abscesses. Antibiotics are, however, sometimes useful to prevent secondary infection. I recommend Oxytetracycline-200 mg/ml (Oxytet, Bio-mycin, LA-200) at the labeled dosage. Anti-inflammatory drugs such as Phenylbutazone (Bute) or DMSO will help reduce the swelling somewhat.
There is no commercial vaccine available although some have tried to vaccinate with an autogenous (made with organisms collected from your own ranch) vaccine. This method has not been proven to be effective yet. For herd management of sheep and goats, isolation and removal of affected animals and thorough cleaning of the environment is most useful. Because of its widespread nature and potential for loss of production, most goat and sheep shows will not accept animals with abscesses For horses and cattle, fly control and equipment sanitation is essential for the prevention of this disease. Cleaning up of discharge from wounds is also useful. A strong iodine or bleach solution is effective for cleaning equipment and burning contaminated dressings is recommended.
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Yesterday, I picked out my horse’s hoofs and there was black foul smelling ‘gunk’ in the frog area. Is that an infection? What can I do about it?
What you see is called thrush in horses. It is an infection of the underside of the hoof and can be treated. The frog is the soft area shaped like a V under the horses hoof. When this area becomes macerated (stays wet for too long) it becomes less able to protect itself from infection. We usually see Thrush during wet periods or in the winter when horses are stabled for long periods of time. The bacteria are variable but usually are opportunistic, that is they take advantage of the right conditions. And although rarely a cause of lameness itself, Thrush can eventually allow exposure of the underlying tissues and cause lameness. Treatment usually consists of trimming the effected areas. Clean and dry the hoof. Next apply a copper or formaldehyde based solution to the affected area and wrap the hoof in a water proof bandage or boot which will keep out feces and water. If the disease gets severe, antibiotics are occasionally necessary. Signs of increased severity would be lameness or exposure of the underlying structures of the hoof (under the skin and hoof).
Finally, prevention is the most effective cure. Thrush can be prevented by keeping the hooves picked and dry. In the winter, frequent cleaning of stalls or turning out will help.
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Winter is the time of year for colds and flu in people. Just like people, horses can get a cold or the flu. In people it has been shown that abrupt changes in weather and working in poorly ventilated spaces can contribute to catching a cold. Abrupt changes in weather and close quarters in stables are also factors in horses. Most colds and flu’s are caused by viruses. The most common viral respiratory disease of horses is Equine Influenza . It is cause by Equine Influenza-1 Virus. Outbreaks of this disease can spread rapidly. The virus incubates with no symptoms for 1-3 days in the horse. Symptoms can spread through a herd in 7-10 days and horses shed the virus for up to 8 days. Some horses show no symptoms and carry the virus. These horses shed the virus and get other horses sick while remaining healthy themselves. Affected horses are lethargic, depressed and off-feed. They will have discharge from there eyes and/or nose and usually have a hacking dry cough. This disease might be mistaken for strangles or equine distemper ( you can read about strangles in the last article by my lovely and talented wife.), however there is no swellings in this disease. All affected horses should be treated and isolated. All horses can be vaccinated twice yearly.
Another common respiratory virus in horses causes Equine Viral Rhinopneumonitis. The virus in this case is Equine Herpes Virus. There are three different types of Equine Herpes Virus which can cause respiratory disease in groups of horses. EHV-4 causes respiratory disease similar to flu. EHV-1 can cause respiratory disease and then abortion four months later….this is why it is necessary to vaccinate all pregnant mares at 5, 7, and 9 months. And EHV-3 can cause respiratory disease in young foals. The signs of herpes virus infection in horse can range from no signs at all to severe lethargy, coughing and discharge. In foals EHV-1 infection causes the disease ‘Snots’ which , you guessed it, causes severe nasal discharge. Vaccinations for EHV are usually given in the fall to mares and stallions or geldings who will be in contact with mares. Also it is very wise to avoid bringing new horses in contact with pregnant mares because of the risk of transmission of the virus.
If left untreated, most cases of equine viral respiratory disease cure themselves. However, sometimes a secondary bacterial infection will result if the horse is too weakened from the virus. These animals are at great risk and so it is probably best to treat all horses with respiratory disease early. Antibiotics to protect against secondary infections, and Non-Steroidal Anti-Inflammatory medicines to combat fever are useful. And like the human doctors say, “get rest and plenty of fluids”.
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How healthy are your horse’s feet? Does your horse have cracked hooves ? Does he/she loose shoes? Do you fight with infected or soft feet? Presented here is some information taken from an article written by a Bob Peacock, a respected farrier, on equine nutrition and how it relates to hoof health and growth. Pay a visit to the best hoof care website, http://www.horseshoes.com/and keep reading to find out how you can help your horse and his/her feet….
DL-methionine is the most important amino acid for hoof growth. It helps prevent edema, or soft-tissue swelling, and infection. Biotin is the second-most important nutrient in hoof growth and repair. It helps alleviate eczema and dermatitis through utilization of proteins. Vitamin A promotes tissue growth, strong bones and hoof, healthy skin, hair, teeth and gums. It also helps build resistance to disease. Vitamin D helps properly utilize vitamin A, calcium and phosphorus, necessary for strong bones, teeth, and the hoof. Vitamin E helps to retard cellular aging, as an antioxidants. It supplies oxygen to the cells for better endurance, helps fight hoof wall fatigue, accelerates hoof healing and growth. Other important nutrients that affect hoof growth and quality are calcium, lysine, selenium and zinc. A few or even all of these can be lacking in the equine diet in effective, hoof repairing amounts. Providing a loose salt/mineral/vitamin mix containing calcium and phosphorous or feeding a hoof supplement will prevent most deficiencies.
The critical results of very minor nutritional problems a farrier sees are cracking of the wall, scaly, dry hooves, hollow wall and hoof wall infection, commonly known as “white line disease.” For horses with these types of problems, a hoof supplement can provide remarkable improvement or even resolution.
However, using a hoof supplement is not the entire answer. The horse should be kept on clean, dry footing. This is not always possible at all times, particularly during “mud season”, but having a dry place for the horse to stand part of the time is helpful. Picking a horse’s feet out every day and even twice daily when conditions are wet will go a long way to preventing infection and sore feet. In addition, there are many topical hoof dressings on the market, and some of them have their place. However, a good, supplement is generally self-sustaining and does not need a topical dressing to enhance the foot’s natural growth or appearance.
Talk to your farrier about hoof problems and consult your veterinarian when adding supplements to your horse’s diet. Most of all, let us work together for the benefit of our friend, the horse.
Ask about hoof supplements that fit your feeding and training program!
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Exercise is a major component of health, well-being, and a long life. This is not ancient oriental wisdom to us in this day and age. This fact is true not only for humans, but also for each of our animal companions without exception. With the warmer weather and show season coming our way, many of us turn our thoughts to getting our equine friends back into condition for the show ring, for work, or for play. Being careful to not overwork your horse too quickly can take you and your horse a long way from becoming injured on your road to fitness.
Now before throwing that saddle on and getting to work, take a step away from your horse and look at him/her for a few minutes. Think about what your horse might need to put him/her in a position to do their best for you. Is it a good tooth floating? De-worming? Vaccines? Does he/she need to have their feet trimmed or shoes on? Have you though about the right feeding program for your horse’s level of work? Is your equipment in shape and clean? Does it still fit your horse? Do you have the equipment or attire for what you and your horse are doing? Whew! Now that our homework is done, let’s get to the fun part … riding!
It is just as important for your horse to stretch out before and after work as it is for us to do so. It is possible to stretch your horse out by you manually stretching his/her legs. Also, walking or trotting in tight circles in both directions while you warm up helps, as does working in an extended trot. Starting your horse off with slow easy work and progressing to harder exercise is the ticket! The best way to do this is to make a plan that works for your horse and you. Start by combining some walking and trotting for 3-5 days a week for one or two weeks. Progress to longer distances or more time as the days go by. On the second or third week, begin working a lope or cantor into the middle of your routine (when your horse has loosened up some). As before, move to longer distances or more time as you go. Your plan needs to be flexible and you need to pay attention to how well you horse is adjusting to the program. Take notice of how long it takes your horse to cool off or catch a breath or slow a heart rate after work. Your cool down/recovery times need to be quick before moving up in your fitness program.
There are risks to be aware of when getting horses back into shape. Colic, of course, is one of them. Another hazard is “tying-up”, or azotemia. Symptoms of “tying-up” are trembling, muscle cramps, a stiff or stilted gait, or an inability to move. Proper feeding, adequate water, and gradual work are the best preventatives for both of these problems. Simply having overly sore muscles is many times another problem our horses run into. A little time off, some “bute”, and a good liniment massage works wonders for this. As before, pay attention to what your horse is telling you. As always, call your veterinarian with any questions or concerns. Dr. Kerri has more info on conditioning your horses! Good luck and have a great ride!
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