HomePhilippine Journal of Veterinary Medicinevol. 49 no. 1 (2012)

Changes in the Anterior Presentation in Sheep Fetuses Due to Their Ventro-Sacral Position in the Second Half of Gestation

Slobodan Sekulić | Aleksandar Bozic | Marija Zarkov | Goran Kekovic | Jelena Podgorac | Aleksandra Novakov-mikic | Ljiljana Martac | Tomislav Barna | Aleksandar Milovanovic | Ivan Pusic | Dragica Stojanovic | Nenad Pepelcevic

Discipline: Veterinary Medicine




The hypothesis tested was that fetal postural development causes anterior presentation of the sheep fetus during a period of exclusive increase in anterior presentation. Exposing fetuses to a ventro-sacral position during a period of equal incidence of anterior and poste­rior presentations [50th-90th gestation day (GD)] should not cause changes in fetal presen­tation. During a period of an exclusive increase in anterior presentation (90th-140th GD) a ventro-sacral position should cause a 180° turn of the fetus. Singleton gestations with fetus in anterior presentation were included. Ultrasound examinations consisted of three con­secutive two minute scans to determine fetal presentation, and were conducted with the ewe in the following three positions: the upright quadrupedal position, sitting position in which the ewe’s trunk is vertical to the ground; and again the upright quadrupedal position. The Mann-Whitney nonparametric U-test was used. On the 83rd GD (14 fetuses), there were no changes in fetal presentation, whereas on the 86th GD (10 fetuses) (p=0.035 p<0.05) and on the 116th GD (12 fetuses) (p=0.000 p<0.05) fetuses frequently assumed a transverse pres­entation at the second examination position. Further experiments would require the fetuses to be artificially maintained in a ventro-sacral position for a prolonged period.