Use of ultrasound echography for early diagnosis of single and twin pregnancy in the mare.

In 1981 a trial was conducted on 6 Newmarket Thoroughbred stud farms into the use of real-time ultrasound echography (scanning) as an aid to the early diagnosis of pregnancy in the mare. The procedure was found to be practicable and interpretation of the findings was relatively straightforward. Pregnancy was positively diagnosed from as early as 14 days after ovulation and a number of twin pregnancies were recognized, some in which the conceptuses were situated in separate horns of the uterus but an almost equal number in which the conceptuses were together in the same horn. It was concluded that the technique of scanning will become an established part of stud-farm practice because it enables early identification of non-pregnancy and also of twin pregnancy before the critical stage of endometrial cup formation.