Horses may develop EPM after ingesting feed or water contaminated with Sarcocystis neurona, a one-celled organism called a protozoan, that is spread by opossums and carried by other animals. Less commonly, a different protozoan called Neospora hughesi may also cause EPM.

What diseases can horses get from possums?

Equine Protozoal Myeloencephalitis (EPM) is a neurologic disease in horses caused by infection with the protozoan Sarcocystis neurona (SN). SN infects horses when they ingest the organism in contaminated feed or water. The definitive host of this organism is the opossum, which passes the organism in its feces.

What are the symptoms of EPM in horses?

  • Ataxia (incoordination), spasticity (stiff, stilted movements), abnormal gait or lameness.
  • Incoordination and weakness which worsens when going up or down slopes or when head is elevated.

How do I keep possums away from my horse?

Maintain a clean barn or facility

. Maintaining a clean barn can help reduce the attraction of rodents, especially opossums in your facility. When possible, avoid feeding horses from the group and clean up spilled feed immediately to deter attracting wildlife and rodents.

Do horses recover from EPM?

If left undiagnosed and untreated, EPM can cause devastating and lasting neurological deficits. The success rate for treated horses is high. Many will improve and a smaller percentage will recover completely, but 10-20% of cases may relapse within two years.

Do opossums hurt horses?

Opossums can transmit Equine Protozoal Myeloencephalitis (EPM) to horses. It is caused by a protozoal parasite whose eggs are shed in opossum feces. Infected animals show various signs of illness, including symptoms of central nervous system disease.

What can cause neurological problems in horses?

Many diseases can affect horses’ central nervous systems, but four of the most common disorders are cervical vertebral stenotic myelopathy (CSM), equine protozoal myeloencephalitis (EPM), equine degenerative myeloencephalopathy (EDM), and equine herpesvirus-1 myeloencephalopathy (EHM).

Does every opossum carry EPM?

A few types of wild animals and all opossums can be the carrier of the protozoa for EPM. While other animals may carry the protozoa in their body, only opossums can transmit EPM.

Are possums bad to have around horses?

Opossum are carriers of equine protozoal myeloencephalitis or EPM. Grass, hay, and grain contaminated by opossum feces can transmit this incurable and deadly disease to horses.

How do I keep possums out of my barn?

Opossums. Keep your barn and surrounding area clean of all garbage, grain and fallen fruit. The absence of food will help keep opossums away. Cut branches away from the roof of the barn — leave at least 5 feet of space between the roof and the closest branch.

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How do I protect my horse from EPM?

To prevent EPM, opossums should be kept out of the barn and especially away from sources of hay, feed, and water. Keeping cats or dogs loose in the barn might help discourage midnight raids by opossums on the feed.

Is EPM in horses painful?

Horses that are suffering from EPM will also be painful around the occiput and atlas, due to the inflammation going on in the spinal cord. If you have the horse walk and have someone walk behind them and pull them by the tail off to one side, they will be unable to right themselves.

How long does it take for a horse to show signs of EPM?

Our results indicate that EPM can manifest as long as 90 days after the parasite has crossed the blood-brain barrier (data not shown), but in most of the challenged horses evidence of infection occurred within 30 days and ataxia was present by 60 days.

Is it safe to ride a horse with EPM?

A Horses that recover completely can return to their original intended use. For horses that do recover, the improvement is based on the initial severity of the clinical signs (see box). However, not all horses that “improve” according to the clinical scale are able to be safely ridden again.

Can you jump a horse with EPM?

The location of the damaged nerves also plays a large part in whether or not the horse can return to his former sport (damage to nerves in the hindquarters may mean that the horse will no longer be able to safely jump, but will be sound enough for trail riding)

How does a horse get EPM?

EPM is a neurologic disease that horses get from eating infected opossum feces. Incoordination, muscle atrophy and loss of feeling around the body are a few signs of illness. Keep your horses healthy by storing grain in sealed bins and controlling opossum populations around your barn.

How do you know if your horse is neurological?

Lack of coordination, weakness or paralysis of the hind limbs, muscle twitching, impaired vision, head pressing, aimless wandering, convulsions, circling and coma are some of the severe neurologic effects. Horses typically have non-neurologic signs, too, such loss of appetite and a depressed attitude.

What are signs of neurological problems?

  • Partial or complete paralysis.
  • Muscle weakness.
  • Partial or complete loss of sensation.
  • Seizures.
  • Difficulty reading and writing.
  • Poor cognitive abilities.
  • Unexplained pain.
  • Decreased alertness.

What does a horse seizure look like?

The most common sign of epilepsy is seizures. The horse will usually become unconscious, collapse, tremble and shake. Its ears or tail may tremble, while its eyes will glaze over, giving a distant or vacant appearance. It is something very disconcerting to witness.

What is Cushing's disease in horses?

Equine Cushing’s disease is a complex progressive disease of the pituitary gland of middle age to older horses. The pituitary gland is a small structure located at the base of the brain which produces hormones that regulate many body functions.

What does strangles do to horses?

Strangles is a highly contagious disease of the equine upper respiratory tract caused by the bacterium Streptococcus equi subspecies equi (S. equi). The bacteria cross mucous membranes in the nose and mouth to infect lymph nodes where they cause abscesses that can eventually rupture.

Are opossums good or bad?

Opossums, sometimes referred to just as possums, are a benefit to ecosystems and a healthy environment beyond eradicating ticks. They will catch and eat cockroaches, rats and mice – in addition to consuming dead animals of all types (also known as carrion).

What do possums hate?

They even hate mothballs and can’t stand the smell or sight of them. Although they hate the smell of ammonia too, we advise you to stay away from it to avoid any health hazards caused due to exposure. Possum repellents can be an effective solution.

Where do possums nest?

Opossums don’t create their own nests. Instead, they take refuge in natural shelters or abandoned nests from other creatures. Logs, brush piles and hollow trees are some of the more popular spots for opossums, so remove these items from your yard.

Do possums keep snakes away?

Possums even hunt venomous snakes that could actually put your family at risk. If you happen to live in an area that has rattlesnakes or copperheads, you might find that a possum can actually help keep your family safe by keeping poisonous snakes away from your children.

What animals transmit EPM to horses?

The causative organism is a protozoal parasite called Sarcocystis neurona. The disease is not transmitted from horse to horse. Rather, the protozoa are spread by the definitive host, the opossum, which acquires the organism from cats, raccoons, skunks and armadillos and possibly even from harbor seals and sea otters.

What are horse wobblers?

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.

What are the signs of a horse going blind?

  • Pain in the eye.
  • Inflammation.
  • Cloudiness in the eye.
  • Change of eye appearance.
  • Reddened eye.
  • Eyelid swelling.
  • Tears.
  • Squinting.