Figure 1From: A preliminary study on the induction of dioestrous ovulation in the mare – a possible method for inducing prolonged luteal phaseProgesterone levels in hCG treated mares that ovulated after treatment. 'a' and 'b' = peaks associated with formation of corpora lutea. * = samples taken 8 or 9 days apart. Dashed lines show the cut-off levels for progesterone samples taken twice weekly (3 nmol/l) or once weekly (10 nmol/l)Back to article page