Decoding moody mare syndrome: Retrospective study and tiered diagnostic framework

Behavioral issues, such as persistent or strong estrus, non-specific pain, and performance challenges in mares are frequently attributed to the estrous cycle.

The objectives of this study were to analyze retrospective data on mares presented for estrus-related behavioral complaints, and to propose a structured diagnostic framework for categorizing cases during work-up at different levels of care.

A retrospective study was conducted using patient records of a total of 14993 mares.

In this data set, behavioral problems, pain, or poor performance were not repeatably verified to be associated with estrus in any mare. Most mares (56.8%) presented with persistent or strong estrous behavior were in diestrus at the time of presentation, suggesting misinterpretation of equine behavior. Recurrent colic, non-specific pain, and symptoms related to urination were more common in geldings than in mares. Internal medicine issues were the most common diagnoses, and they were associated with a specific stage of the estrous cycle (diestrus). Aggressive behavior was significantly associated with orthopedic diagnoses. A tiered diagnostic framework was proposed to improve client compliance, diagnostic accuracy, and management strategies, as the association between the stage of the estrous cycle and various behavioral or pain-related symptoms in the mare may be overestimated by both owners and clinicians.

In conclusion, the diagnostic approach should include repeated and thorough gynecological examinations with detailed record-keeping to verify the role of the estrous cycle in each clinical case, and internal medicine or orthopedic diagnostics should be pursued as indicated.