FIGURE 3.

(a) Power Doppler ultrasound of a functional CL of 8 days postovulation in a mare. The day 8 postovulation is the day with the highest blood supply to the CL and with the highest production of progesterone. Power Doppler ultrasound is the most sensible technique to assess the vascularization of CL. (b) Endometrial blood flow evaluated with power Doppler ultrasound. Computer‐assisted pixel analysis using Image J software has been performed in research work in order to semi‐quantitatively evaluate the vascularization and echotexture of different organs based on the area and intensity of pixels identified in the image