Why Might a Non-Pregnant Mare Produce Milk?
It is not typical for a mare that is not pregnant to produce milk, particularly if she has had no contact with a stallion. This situation usually points to an underlying issue.
Possible Causes
Hormonal Imbalance: Conditions such as pseudopregnancy, where a mare shows signs of pregnancy without being pregnant, can trigger milk production. Tumors in the pituitary gland or ovaries, or conditions like Cushing's disease, may also disrupt hormones.
Stress and Environment: While less common, extreme stress, dietary changes, or exposure to other lactating animals could theoretically influence milk production.
What to Do
Consult a veterinarian promptly. A vet can perform a physical exam and blood tests to identify the cause and recommend treatment. Monitor your mare for behavioral changes, decreased appetite, weight loss, or udder swelling.
While rare, lactation in non-pregnant mares is possible and typically requires early diagnosis and treatment to protect the mare's health.