Conceptus ecobiometry and triplex Doppler ultrasonography of uterine and umbilical arteries for assessment of fetal viability in dogs

• Published in: Theriogenology Vol. 74; no. 4; pp. 608 - 617
• Main Authors: Miranda, S.A., Domingues, S.F.S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.2010; [Oxford]: Butterworth-Heinemann; [New York]: Elsevier Science
• Subjects: Animals; biometry; Bitch; blood flow; conceptus ecobiometry; diastolic flow; diastolic notch; dogs; Dogs - embryology; Female; Fetal Development; Fetal Viability; Fetoplacental circulation; fetus; Fetus - blood supply; Gestation; hemodynamics; Pregnancy; Pulsatile Flow; puppies; Regional Blood Flow; ultrasonography; Ultrasonography, Doppler - veterinary; Ultrasonography, Prenatal - veterinary; umbilical arteries; Umbilical Arteries - diagnostic imaging; Umbilical Arteries - physiology; Uterine arteries; Uterine Artery - diagnostic imaging; Uterine Artery - physiology; uterus; viability; vigor; whelping; Bitch; Fetal development; Fetoplacental circulation; Gestation; Uterine arteries
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/j.theriogenology.2010.03.008

The objectives were to: 1) evaluate blood flow in the uterine (UA) and umbilical (Uma) arteries in the pregnant bitch, by measuring the resistive index (RI) and pulsatility index (PI); 2) to note the presence or absence of the early diastolic notch and diastolic flow in the UA and Uma flow waveforms, respectively; and 3) perform conceptus ecobiometry for fetal growth assessment during pregnancy. Six healthy bitches were examined on approximately Days -44, -42, -36, -31, -28, -25, -21, -18, -14, -8, -4, and -2 of pregnancy (whelping = Day 0). Triplex Doppler and B-mode ultrasonography were used to assess blood flow and conceptus ecobiometry. All pregnancies ended with a normal whelping and birth of live puppies. Prior to whelping, all conceptus dimensions increased significantly, whereas RI and PI of both the Uma and UA decreased significantly. For the UA, RI and PI were (mean ± SEM) 0.95 ± 0.02 and 2.75 ± 0.41, respectively, on Day -44, and were 0.60 ± 0.01 and 0.99 ± 0.03 on Day -4. For the Uma, RI and PI were 0.99 ± 0.01 and 2.42 ± 0.03 on Day -31, and were 0.62 ± 0.01 and 1.15 ± 0.02 on Day -4. The complete disappearance of the early diastolic notch in the UA, and the appearance of diastolic flow in the Uma occurred on Days -16 ± 5 and -21 ± 1. The authors concluded that UA and Uma perfusion were important end points to assess fetal vitality in bitches. Furthermore, the current reference values provided a baseline for monitoring normal and abnormal pregnancies in bitches.