The Educated Horseman: Disease Series

Foal Deworming

When spring arrives, so does another foaling season, welcoming a crop of foals and, with it, concern for the parasite load in young horses. Foals are typically more susceptible to parasites, and while we are all deworming our horses based on fecal egg counts, this approach is not recommended for foals.

For more information, click on the link below.

P3927-A Foal Deworming

Equine Pythiosis

Equine pythiosis, commonly referred to as swamp cancer, is becoming more prevalent in horses across the southern region. Pythiosis is a fungus-like infection that can affect the skin, bones, intestines, lungs and arteries of horses and other animals. It is caused by the organism Pythium insidiosum. Pythium insidiosum is traditionally thought of as an aquatic fungi or water mold and typically occurs in wetland conditions. However, floods and heavy rains can spread the organism to new areas.

For more information, click on pdf link below.

Pub. 3609 - Equine Pythiosis

Blister Beetle Toxicity in Horses

blister beetle

Tips to reduce the chance of blister beetle poisoning:

  • Buy hay from local producers, if possible. Develop a relationship with your hay producer and be aware of his or her production practices.
  • Buy first-cutting hay, when blister beetles are not active.
  • Look for hay that is harvested at the late bud stage or when the first flowers open.
  • Learn to recognize blister beetles and understand their behavior.
  • Check all hay prior to feeding for the presence of blister beetles.

For more information, click on pdf link below.

Equine Enteric Coronavirus

Equine enteric coronavirus has been diagnosed in Louisiana by the LSU School of Veterinary Medicine. Coronaviruses are part of a larger a large group of RNA viruses that can cause both respiratory and intestinal distress in a variety of species, including birds, dogs, cats, swine, cattle, horses and humans.

For more information, click on pdf link below.

Mosquito-borne Equine Diseases


When mosquito season arrives in Louisiana, it’s generally accompanied by two diseases that potentially are fatal for your horses. West Nile virus and eastern equine encephalomyelitis are prevalent in Louisiana and can cause death in horses.
Many cases of both West Nile and EEE are reported annually across Louisiana. The majority of those cases could have been prevented by vaccinating horses.

For more information, click on pdf link below.

Preventing West Nile Virus in Horses

West Nile Virus is a viral disease that can cause encephalitis or meningitis – an infection of the brain and spinal cord or their protective coverings. The virus is transmitted to horses by the bites of infected mosquitoes.

Horses are considered to be “dead end hosts” for West Nile virus, meaning the virus is not directly contagious from horse to horse. Horses that become infected with West Nile virus may have a loss of appetite, depression, fever, weakness or paralysis of the hind limbs, muscle spasms or twitching, impaired vision, lack of coordination, head pressing, aimless wandering, convulsions, inability to swallow, circling, hyperexcitability or coma.

For additional information, click on pdf link below.

The Battle Against Rain Rot

rain rot

Rain rot is extremely contagious. Practicing good hygiene and biosecurity techniques are important to prevent the spread of this infection. These are a few of the techniques that can help reduce the spread of rain rot:

  • Groom your horse daily with clean brushes.
  • Isolate infected horses.
  • Clean contaminated equipment before using on another animal.
  • Use an insect spray to reduce skin trauma.
  • Avoid sharing grooming kits.
  • Reduce environmental factors, when possible (constant wet/humid conditions).
For more information, click on link below.

Recurrent Airway Obstruction (RAO) in horses

coughing horse

Recurrent Airway Obstruction (RAO), formerly known as chronic obstructive pulmonary disease (COPD), or heaves, is a disease of the equine lung. RAO is a chronic, non-infectious airway condition in horses that is a result of an allergic reaction to inhaled particles such as, mold or dust found in feed or bedding.

For more information, click on pdf link below.

Anhidrosis in Horses

Increased heat and humidity across the Southeast has caused a rise in an equine condition known as anhidrosis. This condition impairs the horse’s ability to regulate its body temperature by sweating. A normal horse loses approximately 65 to 70 percent of its body heat from evaporation of sweat, while only 15 to 25 percent of heat is lost through respiration; therefore, the inability to sweat in hot, humid climates can become a serious health threat.

For more information, click on the pdf link below.

Pub The Educated Horseman - Disease Series - Anhidrosis in Horses_FINALpdf

Vesicular Stomatitis in Equine

Ten horses in southwest Texas were diagnosed with vesicular stomatitis in 2014. Farms in Kinney, Hidalgo, Nueces and San Patricio counties are under quarantine by the Texas Animal Health Commission. 

Because of the increasing number of confirmed cases of vesicular stomatitis, animal health officials with the Louisiana Department of Agriculture and Forestry are requiring additional documentation on horses entering Louisiana from any state with confirmed cases of vesicular stomatitis.

coughing horse
5/16/2024 3:03:08 PM
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