Application of Doppler Ultrasonographic Assessment of Maternal and Foetal Blood Flow in Canine Pregnancy
Doppler ultrasonographic assessment of maternal and foetal blood flow has become an indispensable diagnostic tool in veterinary obstetrics and gynaecology.
To evaluate blood flow in uteroplacental artery (UPA), umbilical artery (Uma) and foetal abdominal aorta by measuring pulsatility (PI) and resistive indices (RI).
Doppler examinations were conducted from fourth week of pregnancy at 10 d interval in twenty apparently healthy bitches of different breeds presented at University Veterinary Hospital, Thrissur, Kerala.
Throughout the study the UPA showed biphasic wave. Up to 40 days of gestation the UPA showed diastolic notch and from 41–50 days it completely disappeared. The PI and RI decreased significantly at 5 percent level between each 10 d interval. Similarly, the PI and RI of Uma decreased significantly at 5 percent level between each 10 d interval. The PI of foetal abdominal aorta increased significantly at 5 percent level from ≤30 d to 31–40 d of gestation and thereafter it decreased significantly up to whelping. During early pregnancy the diastolic wave form was absent for Uma and abdominal aorta, although at later stages both these vessels showed biphasic wave forms. The study also included the diagnosis of an incomplete abortion in a Rottweiler bitch by Doppler ultrasound and its critical management. Fourteen days from the date of the incomplete abortion of three puppies, the bitch whelped five healthy puppies.
The study demonstrated the potential applicability of Doppler Ultrasound in the management of abnormal pregnancy and predicting survival chances of neonates after whelping.