Colour-Doppler ultrasound imaging as a laparoscopy substitute to count corpora lutea in superovulated sheep

This study evaluated colour-Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty-five Santa Ines ewes were superovulated three times at 21-day intervals. Corpora lutea were counted by colour-Doppler UI (CL_DOPPLER ) 6 days after each superovulation and confirmed by laparoscopy (CL_LAP ) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CL_DOPPLER and CL_LAP , respectively) with a significant positive correlation (r = .94; r² =.89). Colour-Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation.