Figure 2

Luteal cross-sectional area and plasma progesterone concentration in cows of group 2 . Luteal cross-sectional area in cows of group 2 that responded to PGF administered on day 5 of the oestrous cycle (n = 5, ─□─) and in cows of group 2 that did not respond (n = 3, ─Δ─) and plasma progesterone concentration in responding (n = 7, · □ ·) and non-responding cows of group 2 (n = 3, · Δ ·) from day 2 to day 9 after PGF. * Significant difference between the two groups in their plasma progesterone concentration. °Significant difference between the two groups in their luteal cross-sectional area and plasma progesterone concentration.