title: Transrectal color Doppler sonography of the A. uterina in cyclic mares.
abstract: Color Doppler ultrasound was used transrectally in 6 mares to locate both the left and right Aa. uterinae and to obtain flow velocity waveforms at defined times (Days 0, 5, 10, 15 and 20) during 4 estrous cycles. Blood flow reflected by the resistance index (RI) was determined for both arteries on 120 occasions. As there was no significant difference and a high correlation in the RI values between the left and right arteries (paired Student's t-test, correlation coefficient r > 0.94; P < 0.05), the average RI value was used for subsequent analyses. There were correlations between RI values, mares and day of estrous cycle (P < 0.0001). The mean RI was higher (P < 0.05) in the 2 multiparous mares (age, 12 to 13 yr) than in the 4 younger maiden mares (age, 6 to 10 yr). During the estrous cycle mean RI values on Day 0 (day of ovulation) and Day 10 were higher (P < 0.05) than on Days 5, 15 and 20, whereas between estrous cycles within mares no differences (P > 0.05) could be measured. The results suggest that transrectal Color Doppler sonography is a noninvasive method for examining differences in impedance to uterine blood flow between different mares and cycle periods.
authors.affiliation: Gynäkologische und Ambulatorische Tierklinik, LMU München, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Bollwein
authors.forename: J
authors.initials: J
authors.lastname: Maierl
authors.forename: R
authors.initials: R
authors.lastname: Mayer
authors.forename: R
authors.initials: R
authors.lastname: Stolla
mesh_terms: D000818:Animals; D001158:Arteries / Q000000981:diagnostic imaging / Q000502:physiology; D001783:Blood Flow Velocity / Q000662:veterinary; D004971:Estrus / Q000502:physiology; D005260:Female; D006736:Horses / Q000033:anatomy & histology* / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D018615:Ultrasonography, Doppler, Color / Q000662:veterinary*; D014599:Uterus / Q000098:blood supply* / Q000000981:diagnostic imaging