Equine Endocrine: Understanding Pituitary Pars Intermedia Dysfunction (PPID) often, but improperly called Equine “Cushing's Disease”
As summer approaches, our horses naturally shed their winter coats. However, if your horse seems to be retaining its winter coat longer than usual, it could be a sign of Pituitary Pars Intermedia Dysfunction (PPID).
Pituitary pars intermedia dysfunction (PPID) also commonly referred to as equine Cushing's disease, is a common endocrine disorder seen in horses, particularly in older animals. It is caused by a dysfunction of the pituitary gland, leading to an overproduction of certain hormones, notably adrenocorticotropic hormone (ACTH). This excess ACTH stimulates the adrenal glands to constantly produce more cortisol, leading to a range of clinical signs. Horses affected by PPID may exhibit a variety of symptoms, including:
Abnormal Hair Growth: One of the most recognizable signs is a long, curly, or delayed shedding coat that fails to shed out normally in the spring.
Muscle Wastage: Affected horses may show muscle loss, especially along the topline and hindquarters.
Increased Thirst and Urination: Polydipsia (increased drinking) and polyuria (increased urination) can occur due to the effects of cortisol on kidney function.
Weight Loss: Despite an increase in appetite, horses may lose weight due to metabolic changes.
Recurrent Infections: Immune function can be compromised, leading to frequent infections or delayed healing of wounds.
Laminitis: Horses with PPID are more prone to laminitis, a painful and often life-changing disease affecting the feet.
Diagnosis of PPID in horses involves a combination of clinical signs and blood tests (measuring ACTH levels). Treatment typically involves medication to manage the symptoms and control hormone levels. The drug pergolide mesylate is usually prescribed to suppress the pituitary gland's abnormal activity.
Managing horses with PPID requires regular veterinary monitoring, adjustments in medication dosages as needed, careful dietary management, and attention to hoof care to prevent laminitis. While PPID is a chronic condition with no cure, proper management can significantly improve the horse's quality of life and slow the progression of the disease.
Please contact us for an appointment if you have any questions, concerns or if your horse shows any of these symptoms.
You can read more about PPID at https://bi-animalhealth.com/equine/articles/the-facts-about-ppid