Early Detection of Pregnancy in Mares

It is important in horse breeding that mares need to get pregnant at end of short breeding season. Mares have a short breeding season characterized with ovarian activity and it lasts from spring to autumn in our country. During the season number of regular estrous cycles is very few even if the mares are sound reproductively. Therefore, pregnancy diagnosis as early as possible after breeding remains critically important. Even though clinical methods and laboratory analysis are commonly used, there is still a need for an economical, dependable and practical method for diagnosing pregnancy in early period of pregnancy. In this review, a brief information about physiology of early pregnancy in mares will be given. Furthermore, current pregnancy diagnosis methods (estrus detection, rectal palpation, ultrasonography, measurements of progesterone, estrogen, eCG and early pregnancy factor and gene expressions due to the pregnancy) will be discussed in detail including their advantages and disadvantages. Also, current conceptions about molecular mechanism of maternal recogniton of pregnancy in mare will be evaluated and alternative pregnancy diagnosis methods will be discussed.