Akademik Veri Yönetim Sistemi
Erciyes Üniversitesi Veteriner Fakültesi Dergisi, cilt.23, sa.1, ss.49-58, 2026 (TRDizin)
The aim of this study was to evaluate and compare the diagnostic efficiency of transvaginal (tvUSG) and transabdominal (taUSG) ultrasonography on the 21st, 35th, and 50th days of pregnancy in ewes, using transrectal ultrasonography (trUSG) as the reference method. A total of 100 Awassi ewes in anoestrus were used in the study. Ewes were mated after estrus synchronisation. Pregnancy diagnosis was performed using only tvUSG and trUSG on Day 21 post-mating, whereas on Days 35 and 50, taUSG was additionally applied, allowing the use of all three imaging modalities. In tvUSG, the sensitivity on Days 21, 35, and 50 was 85.71%, 95.34%, and 87.80%, respectively, while specificity remained 100.0% at all time points. The positive predictive value was 100.0%, and the negative predictive value was 87.93%, 96.61%, and 91.18%, respectively. Overall accuracy was calculated as 93.00%, 98.00%, and 95.00% on Days 21, 35, and 50 (Kappa=0.860; 0.959; 0.895, P<0.001). Conversely, taUSG demonstrated a sensitivity of 88.37% on Day 35 and 95.12% on Day 50, with accuracy values of 95.00% and 98.00%, respectively (Kappa 0.897; 0958, P<0.001). When the mean examination times were evaluated, tvUSG had the shortest diagnostic time with 110.03±3.09 seconds and 57.06±1.19 seconds on days 21 and 35, respectively, while taUSG was by far the fastest method with 50.12±1.40 seconds on day 50 (P<0.001). In conclusion, tvUSG emerges as an alternative to trUSG for early pregnancy diagnosis, whereas taUSG is clinically more practical in later stages of gestation due to its ease of application and shorter examination time.