Eating dry or wilted red maple leaves is poisonous for horses, leading to life threatening toxicosis. Storms, high winds, and autumn all result in more leaves on the ground, and it is important to not allow a horse to graze in any place where red maple leaves may fall
Right dorsal colitis (RDC) is an ulceration of part of the large intestine, the right dorsal colon, as a side effect of non-steroidal anti-inflammatory drugs (NSAIDs). Although RDC is usually connected to high doses or prolonged ingestion of these drugs, some cases involve normal usage in inherently sensitive horses.
Rabies is a viral disease affecting the brain that is fatal once symptoms are recognizable. Horses with rabies often present with severe behavior changes such as self-mutilation, aggression, hyperexcitability, uncoordinated gait, and seizures.
Ryegrass staggers occurs when horses ingest a toxic dose of ryegrass contaminated by fungal or bacterial toxins. Lolium, or ryegrass, is a type of grass found worldwide, commonly used in pastures, lawns, and for soil erosion control.
Retained deciduous (or baby) teeth occur when the adult teeth do not push the overlying baby teeth out of the gums as they grow. Normally, the baby teeth become thin, forming a cap on the underlying permanent tooth, and fall off between 2.5 - 4.5 years of age.
Rhodococcal pneumonia is an infection of the lungs in horses. It is caused by the bacteria Rhodococcus equi, which is found in soil. Rhodococcal pneumonia is the most common cause of pneumonia in foals.
Dermatophytosis is a fungal skin infection also known as ringworm. Ringworm is very contagious and is transmitted by contact with infected horses or contaminated materials and surfaces.
Rain rot or rain scald is caused by Dermatophilus congolensis, a bacteria that causes a skin infection in horses. Rain rot affects horses of all ages, but most commonly affects young or immunosuppressed horses chronically exposed to wet conditions.
A horse which groans excessively or ‘roars’ during exercise may have laryngeal paralysis. This condition is caused by damage to a nerve inside the neck which controls the opening of the throat.
Rayless goldenrod toxicosis in horses is a life-threatening condition caused by the ingestion of a toxic dose of the Isocoma pluriflora plant, commonly referred to as rayless goldenrod.
Retained placenta is a common postpartum complication in mares in which the placenta is not expelled within 3 hours of delivering a foal.