Figure 1.

(A) Timeline of the procedures carried out during the study. Black dots (D0, D1, and D5) indicate the moment when Doppler ultrasound analysis was performed. The black square indicates the moment of artificial insemination (AI). (B-i) Detail of the procedure of transabdominal ultrasonography carried out during the analysis. The assay was performed by two researchers, one in charge of the ultrasound probe, while the other was analyzing the real-time images. (B-ii) A representative image was displayed by the ultrasound apparatus (MyLab^TM alpha, Esaote España S.A., Barcelona, Spain) during the evaluation of the uterine arteries of a sow.