Assessment of transrectal ultrasonography for detection of ovarian follicles in hair sheep

• Published in: Archivos latinoamericanos de producción animal Vol. 15; no. 1
• Main Authors: Contreras Solís, I, Díaz, T, López, G, Caigua, A, García, H, Salvador, A, González-Bulnes, A
• Format: Journal Article
• Published: Venezuela Asociacion Latinoamericana de Produccion Animal 29.11.2007
• Subjects: Evaluación; Folículos ováricos; Ovejas de pelo; Utrasonografía
• ISSN: 1022-1301

This study evaluated the accuracy of transrectal ultrasonography (US) for the determination of ovarian follicles in hair sheep. Number and size of follicles in 24 ovaries (n= 12 ewes) were determined using an ultrasound machine (Aloka SSD 500), fitted with a 7.5 MHz transrectal probe. The ovaries were collected just after US, for measurement of the number and size of follicles (postmortem findings; PM). There were no differences in the number of small (2 to 2.9 mm), medium (3 to 3.9 mm), large (≥ 4 mm) and total follicles/ovary as detected by US and PM (1.3 ± 0.3 vs 1.6 ± 0.3; 0.5 ± 0.2 vs 0.8 ± 0.2; 0.5 ± 0.2 vs 0.5 ± 0.2; and 2.3 ± 0.3 vs 2.9 ± 0.4; respectively). The sensitivity and predictive value of US for detection of follicles in each category were 71.1, and 87%; 68.4, and 100%; 91.7, and 100%; 73.9, and 92.7%, respectively; the correlation coefficiennts (r) for number of small, medium, large, and total follicles being 0.75, 0.83, 0.96 and 0,75 (P<0.001), respectively. It was concluded that US is an efficient tool for detection and measurement of ovarian follicles in studies of the reproductive physiology in hair ewes.