Web
Topics
Medical
Info
Pics
and Videos
Products
Return
to Home
EQUINE DENTAL CARE
An excellent Dentistry article from UC Davis Vet School:
http://www.vetmed.ucdavis.edu/ceh/pubs-hreport-24-2.htm
DEWORMING SCHEDULE
While we recommend this schedule, you may find other appropriate routines with a variety of medications. Evaluate the paddock conditions at your barn for appropriate pasture management such as not feeding off the ground and pasture rotation.
JANUARY Ivermectin
MARCH Stongid (pyrantel)
MAY Equimax (with praziquantel for tapes)
JULY Ivermectin
SEPTEMBER Equimax
NOVEMBER Ivermectin
A double dose of Strongid can also be given for tapeworm control.
The Panacur Power pack (double dose of fenbendazole for 5 days) may be
used for weight loss, chronic colic, or diarrhea as it is effective in
controlling encysted small strongyles.
|
Spring
Routine Health Care
Click here for the
QUIZ
VACCINATIONS
Note: If your horse has been sensitive (ex: stiff, sore, lethargic in the days following vaccination) to vaccines in the past, an anti-inflammatory drug (bute or banamine) can be given with the vaccines to lessen or avoid these reactions
Due to maternal antibody interference, routine foal vaccination should wait until 5 to 6 months of age. If there is reason to vaccinate earlier (such as the mare may not have been vaccinated or a disease is active in your area), the vaccine could be administered earlier to the foal but repeated and boostered after 6 months.
Strangles vaccine should be the last vaccine given when multiple vaccines are administered to avoid contamination of other injection sites.
Rabies booster- if a rabid animal has been observed in the horse's area, even without known contact, a booster is appropriate.
Tetanus- booster if the horse sustains a deep puncture wound or a severely contaminated laceration
________________________________________________
FOALS: Rabies, Tetanus, Eastern and Western encephalitis, Influenza and Rhinopneumonitis, West Nile Virus and Strangles all given at 5/6 months and then boostered about 3 weeks later. Potomac Horse Fever may be given to horses under certain environmental conditions (horses living in swampy, wet, streamy areas) or where disease is endemic.
ADULTS: the most common vaccines administered: EW (eastern and western encephalomyelitis), tetanus, and rabies. Our practice expects all horses to be protected yearly with these vaccines as a matter of owner responsibility. Influenza, rhinopneumonitis and West Nile virus, PHF, Strangles are also recommended.
Increased frequency of vaccination: Flu/Rhino, Strangles, WNV and EEE/WEE and PHF may be given 2 to 3 times yearly depending upon reported cases in the area or when horses are housed in larger facilities where horses with unknown vaccination histories move in and out ( boarding stables, shows, racetracks, etc.).
VACCINES
1. TETANUS: absolutely required due to the severity of the disease.
Tetanus is a disease caused by a toxin produced by the bacteria, Clostridium tetani. It generally gains entrance into the body as a result of a deep or penetrating wound such as a puncture. The action of this toxin in the body of an unvaccinated animal is to inhibit the production of a special chemical necessary for the proper functioning of nerves and muscles. When the toxin is released in the horse's body it makes the muscles unable to stop their contractions resulting in prolonged, abnormal muscle firing. The horse is unable to eat or move normally, its muscles become tight and rigid and any stimulation can cause the horse to go into spasms and convulsions. Horses with tetanus will usually die.
Protection against tetanus is easy and inexpensive. Foals are generally vaccinated at about 5/6 months of age followed with a booster 2-4 weeks later. Yearly boosters are then required for the life of the horse. Horses sustaining deep puncture wounds or severe lacerations should be given immediate tetanus protection boosters even if they have previously been vaccinated. Pregnant mares should also have a tetanus booster at about 9/10 months of gestation to pass on immunity to the newborn foal.
2. EASTERN / WESTERN ENCEPHALOMYELITIS - required. There were reported cases in NH and MA in 2007.
These are neurologic diseases caused by viruses. The natural reservoir in the environment is birds and horses become infected by the bite of a carrier mosquito. The horse is not a natural host for this virus so it is called a "dead end" host, meaning it does not serve as a source of infection for other horses or people. The effect of the virus is on the brain and causes signs such as aimless wandering, head pressing, profound depression, convulsions and death.
Protection against encephalitis should be routine and in most cases the vaccines against tetanus and encephalitis are combined in a single injection. As with tetanus, foals are vaccinated at about 5/6 months of age with an initial injection and then a follow-up booster 2-4 weeks later. Yearly boosters are then given for the life of the horse. Pregnant mares should be vaccinated at about 9/10 months of gestation.
3. RABIES: absolutely required due to the severity of the disease and the risk of human exposure. Reported in all New England states.
Rabies is a viral disease that is spread exclusively through the bite of an infected individual. It is always fatal and can affect people as well as animals, including horses. The reservoirs of infection in nature are primarily skunks, foxes, raccoons and bats. The incubation period of the disease is variable as are the clinical signs. Any obvious bizarre changes in behavior accompanied by weakness and incoordination should be viewed with caution and veterinary attention secured. Foals should be vaccinated at 5/6 months, ~3 weeks later and then annually.
4. INFLUENZA AND RHINOPNEUMONITIS: recommended for horses in group situations.
These are both upper respiratory viral infections that are spread primarily through direct contact with infected individuals or their nasal secretions. In general they cause fever, cough and nasal discharge (snotty nose). The virus is often spread throughout a barn or stable affecting many of the horses. Most of the time the disease will run its course without complications but occasionally pneumonia or other more serious complications can occur. In addition to the most common upper respiratory form of rhinopneumonitis, variants can cause abortions in pregnant mares and rarely, neurologic disease. Vaccinations against "flu" and "rhino" begin in foals at about 6 months of age followed by a booster in 3/4 weeks. Some recent literature has indicated that 3 initial injections may offer the best protection (see AAEP recommendations). Depending upon the degree of exposure to other horses, boosters may be given every 3-6 months. Exposure is at its highest with stabling, showing, or traveling.
Pregnant mares should be vaccinated against rhinopneumonitis at 3, 5, 7 and 9 months of gestation.
5. POTOMAC HORSE FEVER: recommended for horses living in marshy, swampy or streamy area
This disease is uncommon in our practice area although it does occur and can be fatal. The disease is caused by an organism called Ehrlichia risticii and is thought to be ingested by the horse while grazing or drinking in or near wet or marshy pastures and streams (actually acquired by the ingestion of small water insects (ex: mayflies and caddis flies). The clinical signs include fever, diarrhea, and laminitis and making a definitive diagnosis of PHF may be difficult. Vaccinations begin at 5/6 months of age followed by a booster in 2-4 weeks and 2x yearly thereafter. Since the vaccine is reported to drop off in protection after 4 months, some researchers recommend that this vaccine be given 3 to 4 times per year in problematic regions.
6. STRANGLES: recommended when horse resides in groups of transient horses, and especially if strangles is endemic to the property.
Strangles is a respiratory disease that is transmitted from one horse to another either by direct contact, through the nasal secretions or through contaminated objects (fomites). This bacterial disease is very contagious and can rapidly spread through a stable or barn. It is characterized by fever, purulent (pus) nasal discharge and painful enlargement and abscessation of the lymph nodes under the jaw possibly causing airway obstruction. Horses may be reluctant to eat and swallow.
The nasal discharge can lead to an accumulation of mucus, rattling breathing noises, increasingly thick discharge and difficulty breathing. The skin over the swollen nodes may ooze fluid as the abscess matures. It may break open itself but these lymph nodes often have to be surgically drained. The disease usually responds well to antibiotic treatment once the lymph nodes have drained. Strangles can also be an ongoing problem on a farm because the organism can survive in the environment for long periods of time and continue to serve as a source of infection. Additionally, horses can become inapparent (clinically normal) carriers of the disease and periodically shed the organism (Streptococcus equi) thereby continuing to transmit the disease to other horses. Vaccination for this disease involves 2 intranasal doses given 2-4 weeks apart starting at 5/6 months and then boostered once or twice yearly thereafter. Protection from the vaccination is not complete but definitely increases the horses's resistance to the disease. Vaccination against strangles is usually done on horses residing in stables where the disease has been present in the past or traveling to areas or stables, shows, etc. where the previous vaccination histories of the other horses is unknown. Younger horses are affected more often than older horses. The bacteria can move to other parts of the body such as chest, abdomen or brain and is known as “bastard strangles”. The immune-mediated disease purpura hemorrhagica can be a sequella of strangles. This can be a life-threatening situation as blood vessel walls become edematous, weakened and can leak fluids resulting in head and limb edema and the sloughing of skin.
7. EQUINE PROTOZOAL MYELITIS: EPM vaccine available under certain circumstances but is of questionable efficacy.
The vaccination for this disease has only been available for a few years and is not one of the routine vaccines. It is given as an intramuscular injection initially and then 2-3 weeks later. The disease is caused by the organism Sarcosystis neurona which is ingested by the horse in feed contaminated by opposum feces. The natural reservoir of the organism is in wild birds. Once ingested by the horse the organism travels to the brain and spinal cord where it can cause a wide variety of signs ranging from obscure lameness to muscle wasting to severe incoordination and paralysis. This disease, also known as EPM is now the most commonly diagnosed neurologic condition in the horse. Diagnosis is made on the basis of clinical signs and blood and cerebrospinal fluid analysis. There is treatment available although it is quite expensive and not always successful. EPM and WNV may share some similar neurologic signs.
Life cycle of S. neurona, the cause of EPM.
Route of infection for EPM in a horse.
8. WEST NILE VIRUS: This is a recommended vaccine since we have had no adverse reactions and because the vaccine is effective (96% effective as shown in studies and by the fact that the incidence of WNV was greatly reduced after vaccines were initiated). Also, according to the CDC, there was a significant increase in human cases in 2003 (no human vaccine available) while there was a relative significant decrease in equine cases (They noted the widespread use of the WNV vaccine).
West Nile Virus is a disease caused by a virus that is transmitted by mosquitoes that have bitten infected birds. Horses and people can be similarly infected by these mosquitoes. Horses do not transmit the disease to each other or to humans.. The disease is characterized by depression, listlessness, incoordination, weakness, stumbling, convulsions and sometimes death. Once a horse is down, the mortality rate is about 70%; however, overall mortality has been reported to be between 30% and 40%.
Examples of body positioning in many neurologic conditions such as WNV, EEE, EPM, EHV 4, etc. or even with traumas such as falls..
WNV – more info and websites of interest
http://diseasemaps.usgs.gov/ human and veterinary information
http://www.cdc.gov available on sites listed
http://www.aphis.usda.gov
This viral disease causes an infection of the brain in birds, humans, horses, dogs, and recently in alligators, cats, goats, and seals. There is no vaccine for humans. The equine vaccines offer excellent protection. Since there are no signs of WNV that completely distinquish it from other neurologic diseases, a diagnostic work-up is needed. The incubation period of the virus is 3-15 days. Blood work can confirm the diagnosis. Most people with WNV are asymptomatic, with a small proportion developing a mild fever, headache, body aches, skin rash, and swollen lymph nodes. Less than 1% of people will go on to develop meningitis or encephalitis with symptoms such as disorientation, tremors, muscle weakness, coma, and paralysis.
Treatment includes supportive care such as respiratory support, intravenous fluids, and prevention of secondary infections in both horses and people. Because WNV has spread quickly throughout most of the country and is potentially fatal, we strongly recommend vaccination. The most recent recommendation is an initial vac. at 5/6 mo. followed by a booster given at 3 to 5 weeks, then a twice yearly vaccination. In areas where the disease is expected to be active, foals can be vaccinated earlier followed by 2 boosters.
In our area, initial vaccination should be started in March so that the booster is completed before the appearance of mosquitoes in May; although it known that WNV more commonly appears after June 15. Additionally, like the Flu and Rhino vaccines, it is further recommended that WNV vaccine be administered 2x yearly for enhanced protection. In other highly affected areas of the country, some vets are recommending vaccination three times per year. Remember, pregnant horses that have not been vaccinated with WNV will need to start the vaccinations early enough in the pregnancy so that all boosters are completed before the 10th month of gestation.
In general this disease has moved westward and there have been no reported cases in either VT or NH in the past 2 years. The CDC reported 98 fatal human cases in the US in 2007. For 2008, the CDC expects WNV cases to peak from the Dakotas to Colorado to California. Some increase is expected along the Gulf coast. The human vaccine should be available within 3 years. As with other mosquito-borne diseases, the property owner should dry up or fill possible mosquito breeding sites. Repellents are recommended.
_________________________________________________
LYME DISEASE (no vaccine)
Lyme disease is caused by the bacteria Borrelia burgdorferi which
is spread by ticks including the small deer tick in our region of the
country. Ticks are always part of this tranmission to mammals.
When immature, this tick (Ixodes dammini) may acquire B.burgdorferi
from a white footed mouse. Then as an adult it feeds on the whitetail
deer where it can acquire the bacteria from or pass on the bacteria
to the deer. At this point the adult tick can also infect horses, dogs,
cows, and humans as well. The tick must remain attached for 24 hours to transmit the disease. About one third of all horses in the northeast may have been exposed to the Lyme disease organism. When the tick feeds it deposits the bacteria which may spread throughout the body and eventually
cause swollen lymph nodes, fever, lameness that can move from limb to
limb, and various other symptoms such as limb edema, muscle
tenderness and hyperesthesia (skin sensitivity), swollen joints, and
lethargy.Traditionally the test for Lyme disease involved taking 2 blood titres 3 weeks apart and looking for a significant increase in antibody levels. However, according to Tom Divers DVM, in the recent Current Therapy in Equine Medicine, a diagnosis can be made when a single titer (via Eliza or Western Blot) is strongly positive,the horse is showing clinical signs, lives in or came from an endemic area, and other illnesses are ruled out. Low titers may show that a past infection has cleared or the infection is so new the body has not yet mounted an antibody defense.The major limitation of serologic tests is that they do not differentiate between active disease and simple exposure to the organism. For this reason, DNA tests are being developed that will directly detect the organism. Treatment: long-term oral doxycycline. Naxcel and IV tetracycline have also been used.Recurrence of signs after treatment has been reported. There may be some irreversible medical problems, so early diagnosis is beneficial. Vaccination: It is reported that some veterinarians are using the canine Lyme disease vaccine in horses, but according to Divers,there is no evidence of its efficacy.
Other vaccines less frequently used in Vt: Botulism, Equine Viral Arteritis, Rotavirus A.
Botulism: used in endemic areas, especially with round bale use.
EVA: used most frequently in reproduction facilities.
Rotavirus A: Vaccinate mares at 8,9, and 10 months of gestation
at each pregnancy. Passive transfer of colostral antibodies helps in theprevention of rotaviral diarrhea in foals. According the AAEP, there is no value of giving this vaccine to foals as there would not be enough time for the foal to develop antibodies when the foal is at risk.
QUIZQUIZQUIZQUIZQUIZQUIZ
1. What is SMZ ?
2. What disease is transmitted by water insects?
3. What is Habronemiasis?
4. What is the average length of gestation in the horse?
5. What are the signs of Cushings disease?
6. What is laminitis?
7. What is the treatment for excessive granulation tissue (proud flesh)? Where on the horse’s body does it most often occur?
8. What is the common name for Strep equi ?
9. What is a "splint" ?
10. What are the signs of "choke"?
11. When is an eye problem an emergency?
12. What drug is essential to have on hand for colic cases?
13. What breeds have ‘feathers’ ?
14. Match the most likely locations for the following tumors:
a. Squamous Cell Tumors 1. Under the tail including anus and perineum
b. Melanoma Tumors 2. Head, limbs, anywhere
c. Sarcoid Tumors 3. Eyes, non-pigmented areas like genitals, mucocutaneous junctions
15. What is the most common tumor in horses?
16. What drug is known to assist with contractions and is used after birthing for a retained placenta?
17. Name 3 causes of a unilateral nasal discharge?
18. What is the difference between analgesics and anesthetics?
19. What is Dex?
20. What is "rain scald or rain rot" ? How is it treated?
21. Why is taking a foal antibody test important?
22. What are the normal equine values for pulse rate, respiratory rate, and temperature?
23. What factor may cause foal vaccination failure?
24. What are 4 clinical signs of inflammation?
25. Name a few of the developmental orthopedic diseases.
26. What is a keratoma?
27. Name the bones of the hoof.
28. Where is the gutteral pouch?
29. When should a pregnant mare be vaccinated?
30. How early can a mare be checked for pregnancy?
scroll down for answers
ANSWERS:
1. SMZ is the antibiotic combination of sulfamethoxazole and trimethoprim. In its 960 mg double strength form the pills are administered as follows: one tablet per 100 lbs twice daily given for five to ten days or more depending on the vet and the horse's condition.
2. Potomac Horse Fever is transmitted by various water insects that are injested orally by the horse when the insects land in feed or hay. The insects such as Mayflies and dragonflies can also be transported in delivered hay that was grown outside of your state.
3. Habronemiasis is an ulcerative skin granuloma common around the world and is caused by nematodes that live in the stomach. The eggs and larvae are passed in the feces and are injested by the maggots of intermediate hosts such as flies. The larvae can invade normal skin and can be swallowed completing the life cycle. Larvae passing into the nose may migrate into the lungs or just into the skin. Other names for the condition include summer sores or granular dermatitis.Warm weather and fly populations increases the incidence of summer sores. Further info can be found on the AAEP website and other sites which will contain pictures. One common lesion is the conjunctival form characterized by yellowish, grainy plaques.
4. Normal gestation averages from 335 to 342 days but the extremes with normal foals has been reported from 305 to 400 days.
5. Cushing disease
6. Laminitis
7. Proud flesh is often seen on open leg wounds. When the healing edges of a wound cannot migrate to close the injury, due to overgrowth of the middle of the wound, the raised area needs to be cut back and treated to keep the middle from continued overgrowth. The vet can cut back the raised area (not painful since the overgrown area does not have a good nerve suppy). The owner will then use a topical med such as DMSO to inhibit any overgrowth, allowing the edges to grow over the wound.
8. Strangles
9. A splint is
10. Signs of choke include feed and water draining from the nostrils and mouth, excessive salivation, inability to swallow and flapping of the lower lip with the head down (coughing, anxiety, retching, and later dehydration and depression).
11. Probably the best criteria to use to determine if a given eye problem is an emergency is whether the horse is showing signs of ocular pain. These signs include squinting (blepharospasm), tearing (epiphora), avoidance of light (photophobia) and a small pupil size (miosis). Any change in the appearance of the cornea itself (cloudiness, spots, hemorrhage, etc.) should also be considered an emergency. As always, if you are unsure as to whether a particular problem is an emergency or not, call your veterinarian.
12. Banamine
13.
14. A3 , B1 , C2
15. Sarcoids
16. The hormone oxytocin
17. A unilateral nasal discharge can be caused by a diseased tooth, a tumor, a sinus condition as examples.
18. These are two pain relievers. Analgesics block only pain while anesthetics block all sensations.
19. Dex is dexamethazone which is a corticosteroid with strong anti-inflammatory properties. In our practice it is used most often for serioius allergic reactions or persistent non-infectious respiratory problems.
20.
21.
22. see the parameters in the emergency section of this site
23. Administering vaccines to a foal that has nursed from a vaccinated mare may cause failure since the maternal antibodies may interfere with the vaccines. If the vaccination has happened as described above with the vaccines given before the age of 5 months, it is recommended that the vaccine and booster be re-administered. This will not be harmful to the foal but it will ensure important disease protection.
24. redness, pain, heat, swelling
25. OCD (osteochondrosis), physitis, angular limb deformities, flexural limb deformities, and the "wobbler" (cervical stenotic myelopathy).
26. A keratoma is an aberrant keratin mass originating from the epidermis of the coronary band often found in the dorsal area of the foot. Its mass may deform the white line allowing infection to enter the area causing pain. Pain may also be caused by the mass compromising tissue leading to necrosis. Treatment can be successful with excision through the hoof wall if possible.
27. coffin bone (P3), navicular bone
28. The gutteral pouches are paired diverticula of the eustachian tubes that in part act to cool the brain. The pouches are folded over the stylohyoid bone creating recesses. If infected pus can exit from the entrance to the pouch which is located caudal to the nasal septum so both nostrils may drain the pus. The gutteral pouches can retain the Strangles organism, strep equi, causing shedding of that organism (even without clinical signs).
29. one month before foaling
30. 14 days post breeding
|
