Alopecia or hair loss in horses can occur for several different reasons and may be temporary or permanent. [1] Alopecia refers to the partial or complete absence of hair that occurs in any area of the body where hair is normally present. [1][2]

Congenital alopecia is a condition that is present at the time of birth. [2] This form of alopecia is non-inflammatory and may occur due to genetic factors, resulting in damage to the hair follicles. [1][2]

Acquired alopecia refers to a partial or complete loss of hair that occurs at any stage of life. [2] It is the most common form of hair loss that affects horses. [2]

Successful treatment of hair loss requires identifying and addressing the underlying cause of the condition. [1] Diagnostic dermatology and blood tests can aid in the diagnosis of acquired alopecia.

Strategies to help prevent hair loss include evaluating your horse’s skin and hair regularly, providing balanced nutrition, and treating injuries and wounds promptly.

Hair Loss in Horses

Alopecia is known to occur in various species, including humans, horses, dogs, cats, cattle, and mice. [1] The condition describes the partial or complete lack of hair in areas where it is normally present. [1]

Types of Alopecia

Depending on the cause of the condition, alopecia is classified as congenital or acquired.

Congenital Alopecia

This form of alopecia is present at birth and occurs because of damage to the hair follicles that may be associated with genetic factors. [2]

Congenital alopecia may or may not be hereditary and does not occur in conjunction with signs of clinical inflammation. There is no treatment for congenital alopecia. [2]

Acquired Alopecia

More common in horses than congenital alopecia, acquired alopecia is not present at birth but can occur at any stage of life. [2] This form of alopecia is classified as either non-inflammatory or inflammatory.[2]

Horses with acquired alopecia are born with normal hair and healthy hair follicles that can produce normal hair. [2] However, acquired alopecia results in the loss of hair due to internal or external factors.

Non-inflammatory causes of acquired alopecia in horses include autoimmune disease, stress factors such as illness, seasonal changes, rubs due to poorly fitted blankets or equipment, nutritional deficiencies, and low thyroid hormones. [2]

Inflammatory causes of acquired alopecia include infections affecting the skin or hair follicles, trauma to the skin and hair follicles, such as burns, allergic skin reactions, and skin cancer. [2]

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The exact number of horses affected by alopecia is unknown.

A retrospective study by researchers at UC Davis determined the prevalence of alopecia areata in various equine breeds was 0.017%. [3]

This study found that Appaloosas and Quarter Horse breeds were most commonly affected by the condition. [3]

Areas on the body where hair loss