Assessment of feline fetal viability by conceptus echobiometry and triplex Doppler ultrasonography of uterine and umbilical arteries

• Published in: Animal reproduction science 2010-12, Vol.122 (3), p.276-281
• Main Authors: Brito, Adriel B., Miranda, Stefânia A., Ruas, Marcone R., Santos, Regiane R., Domingues, Sheyla F.S.
• Format: Article
• Language: English
• Subjects: Animals; arteries; Biometry - methods; blood flow; Brazilian Shorthair (cat breed); Brazilian Shorthair cat; breeds; cats; Cats - embryology; conceptus; echobiometry; Female; Fetal Development; Fetoplacental circulation; fetus; Gestation; Pregnancy; Pulsatile Flow; ultrasonography; Ultrasonography, Prenatal - methods; Ultrasonography, Prenatal - veterinary; umbilical arteries; Umbilical Arteries - diagnostic imaging; umbilical cord; Uterine arteries; Uterine Artery - diagnostic imaging; uterus; Vascular Resistance; viability
• ISSN: 0378-4320; 1873-2232
• DOI: 10.1016/j.anireprosci.2010.09.003

The aims of the present study were to: (1) evaluate blood flow in the uterine (UA) and umbilical arteries (Uma) in the pregnant queen, 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 echobiometry for fetal growth assessment during pregnancy. Eight healthy pregnant domestic Brazilian Shorthair queens were examined from Days 10 to 50 after mating (mating = Day 0). Triplex Doppler and B-mode ultrasonography were used to assess blood flow and conceptus echobiometry. All pregnancies ended with a normal parturition and birth of live kittens. Prior to parturition, all conceptus dimensions increased significantly, whereas RI and PI peaked between Days 33 and 43 followed by a decrease ( P < 0.05). The PI least on Day 50. The RI and PI of Uma decreased ( P < 0.05) during two periods in the fetal development, i.e. from Days 22 to 40 (0.79 ± 0.01 and 1.64 ± 0.04), and from Days 41 to 50 (0.75 ± 0.01 and 1.39 ± 0.05), representing the increased Uma perfusion. Both the complete disappearance of the early diastolic notch in the UA, and the appearance of diastolic flow in the Uma occurred on Day 42 ± 1. It was concluded fetal echobiometry, UA and Uma perfusion, were important end points to assess fetal viability in queens. Furthermore, the current reference values provided a baseline for monitoring normal and abnormal pregnancies in queens.