Acta Vet. Brno 2020, 89: 61-67

Changes in Doppler indices throughout pregnancy in queens

Melih Uçmak, Ozge Turna, Gamze Evkuran Dal, Zeynep Günay Uçmak, Mehmet Can Gündüz

Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Istanbul University-Cerrapaşa, Istanbul, Turkey

Received April 25, 2019
Accepted January 28, 2020

Doppler ultrasonography (D-USG) is a non-invasive technique that has become an increasingly essential tool in veterinary theriogenology. The aim of this study was to evaluate the changes of Doppler indices in the foetal aorta (FA), foetal vena cava (FVC), umbilical artery (UA), and uteroplacental artery (UPA) in pregnant queens, thereby advancing knowledge about Doppler findings in normal feline pregnancy. The study was conducted with 10 pregnant queens with known gestational age. Doppler ultrasonography was performed every three days beginning from the 21st day to the 60th day of pregnancy. The pulsatility index (PI) and resistance index (RI) of FA, FVC, UA and UPA were recorded during the D-USG examinations. Although a declining trend was seen in the mean RI of FA, a comparison with earlier sampling periods revealed that significant decreases (P < 0.05) did not occur until Days 30 and 60. While PI of FVC was relatively constant, RI varied througout pregnancy. The PI and RI of UPA values were significantly lower (P < 0.05) on Day 60 when compared to the first five sampling periods for PI and the first six sampling periods for RI. The study concludes that the decrease in UA indices is a precursor for delivery time in queens. However, there is a need for further comparative studies involving impaired pregnancies.


This research was presented in V. National Congress of Turkish Society of Veterinary Gynaecology, with the support of the Research Fund of Istanbul University (BAP) (Grant number 37251). The authors are also grateful to Prof. Dr. Bülent Ekiz for statistical analysis and Esra Çalişkan Karaçam, DVM for the assistance of Doppler ultrasonography examinations.


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