A series of experiments studied the possible role for prolactin in the spring-time recrudescence of ovarian activity in mares. The first experiment was based on cabergoline administration to seasonally anovulatory mares to prevent the seasonal rise in endogenous plasma prolactin to assess whether reduced prolactin altered onset of ovarian activity or first ovulation. The subsequent experiment tested whether season affected the duration and degree of suppression produced by a standard dose of cabergoline. Mares were administered cabergoline at 1.
Clinical Reproductive Anatomy and Physiology of the Mare
The Mares Reproductive Cycle | EquiMed - Horse Health Matters
However, wide variations in cycle length and ovarian characteristics are associated with normal fertility. Abnormalities of endocrinology, cyclicity, and ovulation are uncommon in mares with normal reproductive tracts, and thus other causes of infertility should be ruled out before implicating abnormal cyclicity as a cause of infertility. Additionally, aging of mares is associated with changes in cyclicity. Abnormal behavior may be related to ovarian pathology, most commonly granulosa cell tumors, in mares. Because this link is known, many other behavioral changes may be attributed to the ovaries by mare owners when in fact they have no association with reproduction. For this reason, mares with abnormal behavior may be presented for examination of the reproductive tract, and it becomes a diagnostic challenge on the part of the theriogenologist to determine the cause of the change in behavior. Diagnosis of the cause of estrous cycle irregularities in mares is based on history, teasing records, findings on palpation and ultrasonography per rectum, and determination of hormone concentrations, when indicated.
Ovarian Tumors - What Horse Owners Should Know
The dynamic functions of the ovaries, uterus, embryo, and fetus are beginning to be fully appreciated as mares are evaluated during different stages of the estrous cycle and pregnancy and during various seasons. Anomalies, injuries and age-related changes may occur in mares, necessitating the use of diagnostic, prognostic, and therapeutic procedures, which require a thorough knowledge of equine anatomy. Several references, including the corresponding chapter in the first edition of this text, are currently available and provide a comprehensive discussion of reproduction in the mare, complementing the information presented in this text. The organs involved in reproductive function are not only physiologically but also morphologically dynamic. The reproductive tract in the mare consists of the ovaries, uterine tubes, uterine horns, uterine body, cervix, vagina, vestibule, and vulva.
Decreased reproductive performance due to summer stress is a well known phenomenon in farm livestock. Whether this occurs in the mare and specifically how this might affect postpartum reproductive activity and performance, especially at Foal Heat FH , is unknown. This study, therefore, aims to investigate this and the factors that might affect postpartum reproductive activity. Reproductive records of Thoroughbred mares mare years bred in subtropical north-western India were retrospectively analysed.