Die Trächtigkeitsuntersuchung bei der Stute

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

• 1 Aurich J E, Brückner S, Scheibenpflug M. Rechtsfragen in der Reproduktionsmedizin beim Pferd. C. Aurich Reproduktionsmedizin beim Pferd. 2. Aufl. Stuttgart; Parey-Verlag in Medizinverlage Stuttgart 2009: 345-369
• 2 Allen W R, Wilsher S. A review of implantation and early placentation in the mare.  Placenta. 2009;  30 1005-1015
• 3 Hendriks W K, Colenbrander B, van der Weijden G C, Stout T A E. Maternal age and parity influence ultrasonographic measurements of fetal growth in Dutch Warmblood mares.  Anim Reprod Sci. 2009;  115 110-123
• 4 Hofmann B, Leiser R, Schuler G. Physiologie und Anatomie der Trächtigkeit, Trächtigkeitsdiagnostik. C. Aurich Reproduktionsmedizin beim Pferd. 2. Aufl. Stuttgart; Parey-Verlag in Medizinverlage Stuttgart 2009: 125-154
• 5 MacPherson M L, Reimer J M. Twin reduction in the mare: current options.  Anim Reprod Sci. 2000;  60–61 233-244
• 6 McCue P M, Thayer J, Squires E L, Brinsko S P, Vanderwall D K. Twin pregnancies following transfer of single embryos in three mares: a case report.  J Equine Vet Sci. 1998;  18 832-834
• 7 Morris L H A, Allen W R. Reproductive efficiency of intensively managed Thoroughbred mares in Newmarket.  Equine Vet J. 2002;  34 51-60
• 8 Nagel C, Aurich J, Aurich C. Determination of heart rate and heart rate variability in the equine fetus by fetomaternal electrocardiography.  Theriogenology. , (im Druck)