Equine perinatology: What we know and what we need to know

Equine pregnancy differs from other domestic species in that the equine foetus matures very late in gestation, maternal progestin concentrations;ise near term, and the foetal gonads enlarge and produce oestrogen precursors. Delivery prior to the final maturational process rarely results in a viable foal. Identification of the compromised equine foetus antepartum is a relatively new approach and treatment protocols for those mares at risk of premature delivery are presented. The role of the foetal pituitary adrenal axis and thyroid stimulating hormone in the final maturation of the equine foetus is discussed. Abnormalities in maternal concentrations of progestins and oestrogens may signal foetal compromise and their role in the initiation of parturition and foetal maturation are briefly reviewed.