Breeding is essential for the future of horse racing, but even those without a passion for the sport can appreciate the pleasure of caring for a brood mare. Pregnancy and birth in horses are joyful occassions, with horse owners discovering new and new and long-lost friends when they announce that a brood mare has conceived!
A successful pregnancy in the world of horse racing, or for any equine species, has the usual pre-requisite that all domesticated mammals share: the brood mare must enjoy normal menstruation with healthy ovulation, be free from disease, and have an integral and normal womb. Brood mares are very expensive to look after with proper care, so her ability to conceive and to deliver a foal need to be assessed as best as possible before major investments in mating her are made.
A three year old brood mare in normal health has the best chance of a successful pregnancy, so owners should consider this age as the best to try for a foal. Late spring and early summer are the best time to mate horses, as there is plenty of feed available during the period of an ensuing pregnancy. High ambient temperature and humidity can be off-putting for horses, and an abundance of flies is most irritating at this time. Breeders routinely transport semen instead of going through the logistics of transporting stallions over long distances. However, traditionalists frown on this technically valid method of conception, and it is actively discouraged in the case of horses with the best pedigrees.
Twins present owners with a great quandry in horse breeding. The vast majority of such cases results in the delivery of dead or weak foals, and can render a brood mare infertile in the future. Abortion or surgical removal may be the only way of avoiding the likely delivery of a weak foal with little chance of normal development.
Modern veterinary obstetrics borrow diagnostic methods from the world of human medicine. It allows breeders and owners to check fertility status, and to discover the delight of a new heart beat as well. Ultrasound is used most commonly, and it can also detect uterine infections which may affect the chances of a successful pregnancy.