Summary
Today, pregnancy diagnosis in the mare is performed by transrectal ultrasonography
on days 17 or 18 after ovulation. If the mare is found not to be pregnant, she can
be bred in the subsequent oestrus again. When performing a pregnancy diagnosis, the
veterinarian has to check for the presence of twins. In mares with double ovulation,
pregnancy diagnosis by transrectal ultrasound should be scheduled for day 14 or 15
after ovulation as manual reduction of twins to a singleton is facilitated before
fixation of the conceptus. A second ultrasound examination should be performed between
days 30 to 35 to allow an early diagnosis of embryonic death. From day 90 of pregnancy
onwards transabdominal ultrasound examination can be performed. Besides ultrasound,
pregnancy in the mare can be diagnosed by determination of pregnancy-associated hormones
such as equine chorionic gonadotrophin, placental progestins or conjugated oestrogens.
However, the determination of these hormones does not allow differentiation between
singleton and twin pregnancies and, in the mare, is considered a supplemental diagnostic
tool, only.
Schlüsselwörter
Stute - Trächtigkeit - Diagnose - Zwillinge - transrektales Ultraschall
Literatur
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, (im Druck)
Prof. Dr. Christine Aurich
Besamungs- und Embryotransferstation
Veterinärmedizinische Universität Wien
Veterinärplatz 1
1210 Wien
Österreich
Graf Lehndorff Institut für Pferdewissenschaften
Brandenburgisches Haupt- und Landgestüt
Hauptgestüt 10
16845 Neustadt (Dosse)
Email: christine.aurich@vetmeduni.ac.at