Geschlechtsbestimmung bei Pferdefeten mittels zwei- und dreidimensionaler Sonografie in der Frühgravidität

Zusammenfassung

Ziel Das Ziel dieser Studie war, erstmals zweidimensionale (2D) und dreidimensionale (3D) transrektale Ultraschalluntersuchungen (USU) hinsichtlich ihrer Richtigkeit und dem zeitlichen Aufwand zur Geschlechtsdiagnose bei Pferdefeten zu vergleichen.

Material und Methoden Zu diesem Zweck wurden 47 Stuten zwischen den Tagen 58 und 115 der Gravidität zunächst einer 2D-USU unterzogen, um das fetale Geschlecht anhand der Lokalisation des Genitaltuberkels oder dem Vorhandensein von äußeren Geschlechtsteilen zu ermitteln. Im Folgenden wurden 3D-Bilder des Fetus angefertigt und anschließend an einem PC ausgewertet.

Ergebnisse Der beste Zeitraum zur Geschlechtsbestimmung war zwischen dem 58. und 79. Graviditätstag mit 77 % (2D-USU und 3D-Bild-Auswertung) korrekten Diagnosen. Durch wiederholtes Auswerten der 3D-Bilder konnte eine Steigerung richtiger Diagnosen um 16 % erzielt werden. Der zusätzliche Zeitaufwand für die 3D-USU und die 3D-Bild-Auswertung betrug etwa 6–7 Minuten pro Stute.

Schlussfolgerung und klinische Relevanz Die Ergebnisse der Studie zeigen, dass die 3D- gegenüber der 2D-Sonografie die Zuverlässigkeit der transrektalen Geschlechtsbestimmung erhöht. Erfahrenen Untersuchern bringt die 3D-Ultraschalltechnik jedoch keine entscheidenden Vorteile und ist zudem zeitaufwendiger.

Abstract

Aim The aim of this study was to compare transrectal two-dimensional (2D) and three-dimensional (3D) ultrasound examination with regards to required time and accuracy of fetal sex determination in early pregnant mares.

Materials and methods For this purpose 47 mares were examined transrectally once between days 58 and 115 of gestation. Initially, the fetal sex was determined by identifying the location of the genital tubercle (GT) or external genitalia using 2D-ultrasound. Subsequently, the ultrasound machine was switched to 3D-mode to obtain images for later computer-based evaluation.

Results The gestational period between days 58 and 79 of pregnancy was the most appropriate time for sex determination with 77 % (2D and first 3D evaluation) correct diagnoses. The accuracy of the sex determination could be increased by about 16 % by a second evaluation of the 3D-images in a minimum time interval of 2 weeks. For each mare the additional time needed to perform the 3D-examination and to assess the 3D-images was approximately 6–7 minutes.

Conclusion and clinical relevance This study demonstrates that the accuracy of transrectal fetal gender determination is higher by using 3D-mode compared to the 2D-ultrasound. For experienced examiners however, 3D ultrasound technology does not offer any decisive advantages and is also more time-consuming.

Schlüsselwörter

Dreidimensionaler Ultraschall - Fetus - Genitaltuberkel - Trächtigkeit - 4D-View - Pferd

Key words

Three-dimensional ultrasound - fetus - genital tubercle - gravidity - 4D-View - horse

• Literatur

• 1 Curran S, Ginther OJ. Ultrasonic diagnosis of equine fetal sex by location of the genital tubercle. J Equine Vet Sci 1989; 9: 77-83 doi: http://dx.doi.org/10.1016/S0737–0806(89)80032–2
• 2 Aurich C, Schneider J. Sex determination in horses – current status and future perspectives. Anim Reprod Sci 2014; 146: 34-41
• 3 Crișan MI, Damian A, Morar I. et al. Equine Embryo Sexing and Ultrasonographic Foetal Sexing – Interests and Applicability. Anat Histol Embryol 2016; 45: 329-337
• 4 Franciolli ALR, Cordeiro BM, da Fonseca ET. et al. Characteristics of the equine embryo and fetus from days 15 to 107 of pregnancy. Theriogenology 2011; 76: 819-832
• 5 Ginther OJ. ed. Ultrasonic Diagnosis of Fetal Sex. In: Ultrasonic Imaging and Animal Reproduction. Cross Plains (Wisc.), USA: Equiservices Publisher; 1995: 236-241
• 6 Holder R. Fetal Sex Determination in the Mare Between 55 and 150 Days of Gestation. AAEP annual convention 2000; 46: 321-324
• 7 Holder R. Determination of Fetal Gender. In: Samper J, Pycock J, McKinnon A. eds. Current Therapy in Equine Medicine. 2nd ed.. St. Louis, Missouri, USA: Saunders Elsevier; 2003: 288-294
• 8 Curran S, Ginther OJ. Ultrasonic fetal gender diagnoses during Months 5 to 11 in mares. Theriogenology 1993; 40: 1127-1135 doi: http://dx.doi.org/10.1016/0093–691X(93)90283-B
• 9 Renaudin CD, Gillis CL, Tarantal AF. Transabdominal ultrasonographic determination of fetal gender in the horse during mid-gestation. Equine Vet J 1999; 31: 483-487
• 10 Livini M. Determination of fetal gender by transrectal ultrasound examination: field’s experience. Proceedings of the 56th Annual Convention of the American Association of Equine Practitioners; Baltimore, Maryland, USA: 4–8 December 2010: 323-327
• 11 Toenissen A, Martinsson G, Otzen H. et al. To perform fetal gender determination in the mare by ultrasound during early and advanced gestation. Pferdeheilk 2015; 31: 153-158
• 12 Resende HL, Carmo MT, Ramires Neto C. et al. Determination of equine fetal sex by Doppler ultrasonography of the gonads. Equine Vet J 2014; 46: 756-758
• 13 Bucca S. Equine fetal gender determination from mid- to advanced-gestation by ultrasound. Theriogenology 2005; 64: 568-571
• 14 Toenissen A, Martinsson G, Pricking S. et al. Transabdominal ultrasonographic determination of fetal gender in the horse during mid-gestation – a comparative study using randomized video images to investigate variation in diagnostic performance among raters, and the effect of month of gestation. Pferdeheilk 2016; 32: 29-35
• 15 Pricking S, Spilker K, Martinsson G. et al. Equine fetal gender determination in mid- and advanced gestation by transabdominal approach – Comparative study using 2D B-Mode ultrasound, Doppler sonography, 3D B-Mode and following tomographic ultrasound imaging. Pferdeheilk 2019; 35
• 16 Stocker J, Evens L. Fetal Sex Determination by Ultrasound. Obstet Gynecol 1977; 50: 462-466
• 17 Birnholz JC. Determination of fetal sex. N Engl J Med 1983; 309: 942-944
• 18 Lev-Toaff AS, Ozhan S, Pretorius D. et al. Three-dimensional multiplanar ultrasound for fetal gender assignment: value of the mid-sagittal plane. Ultrasound Obstet Gynecol 2000; 16: 345-350
• 19 Youssef A, Arcangeli T, Radico D. et al. Accuracy of fetal gender determination in the first trimester using three-dimensional ultrasound. Ultrasound Obstet Gynecol 2011; 37: 557-561
• 20 Kotoyori Y, Yokoo N, Ito K. et al. Three-dimensional ultrasound imaging of the equine fetus. Theriogenology 2012; 77: 1480-1486
• 21 Merkt H, De Andrade Moura JC, Jöchle W. Gender determination in equine fetuses between days 50 and 90 of pregnancy. J Equine Vet Sci 1999; 19: 90-94
• 22 Mari G, Castagnetti C, Belluzzi S. Equine fetal sex determination using a single ultrasonic examination under farm conditions. Theriogenology 2002; 58: 1237-1243
• 23 Curran S, Ginther OJ. Ultrasonic determination of fetal gender in horses and cattle under farm conditions. Theriogenology 1991; 36: 809-814
• 24 Bucca S. Ultrasonographic monitoring of the fetus. In: McKinnon A, Squires E, Vaala W. et al., eds. Equine Reproduction. 2nd ed.. Iowa: John Wiley & Sons; 2011: 39-54
• 25 Becsek A, Tzanidakis N, Blanco M. et al. Transrectal three-dimensional fetal volumetry and crown-rump length measurement during early gestation in mares: Intra- and inter-observer reliability and agreement. Theriogenology 2019; 126: 266-271
• 26 Karadaev M, Fasulkov I, Vasilev N. et al. Three-dimensional (3D) ultrasound investigations for monitoring of the second and third pregnancy trimester in goats. Tradition and Modernity in Veterinary Medicine 2019; 4: 72-76
• 27 Drews B, Hermes R, Göritz F. et al. Early embryo development in the elephant assessed by serial ultrasound examinations. Theriogenology 2008; 69: 1120-1128 doi: http://dx.doi.org/10.1016/j.theriogenology.2008.01.026
• 28 Chandolia RK, Jinsa G. Application of 3D/4D ultrasonography in canine gynaecology & obstetrics. Indian J Canine Pract 2011; 3: 99-102
• 29 Hildebrandt TB, Drews B, Kurz J. et al. Pregnancy monitoring in dogs and cats using 3D and 4D ultrasonography. Reprod Domest Anim 2009; 44 (Suppl. 02) 125-128