Which abnormal condition is characterized by excessive thirst and urination in horses?

The condition characterized by excessive thirst and urination in horses is Diabetes Insipidus. This medical condition results from the horse’s inability to concentrate urine due to a deficiency of the hormone vasopressin (also known as antidiuretic hormone). This leads to frequent urination (polyuria) and compensatory excessive drinking (polydipsia).

Cushing's Syndrome, while it can cause various symptoms in horses such as excessive thirst, it primarily involves a different hormonal imbalance related to the pituitary gland, often associated with issues like coat changes, muscle wasting, and increased appetite rather than the specific polydipsia and polyuria associated with Diabetes Insipidus.

Colitis refers to inflammation of the colon, generally leading to diarrhea and abdominal pain, but does not typically manifest with increased thirst or urination. Similarly, Strangles is a contagious disease that affects the lymph nodes and respiratory system, characterized more by fever and nasal discharge than changes in thirst or urination patterns.

Understanding these distinctions is crucial for identifying and managing each condition accurately in horses.