Post-partum concentrations of serum progesterone, oestradiol and prolactin in Arabian mares demonstrating normal maternal behaviour and Arabian mares demonstrating foal rejection behaviour.

•The aim of the current prospective study was to investigate possible endocrine components to foal rejecting behaviour in Arabian mares.•Oestradiol and prolactin concentrations did not differ significantly between mares that accepted or rejected foals.•Progesterone and prolactin concentrations decreased from days 1 to 3 post-partum in both rejecting and non-rejecting mares.•The oestradiol to progesterone ratio was higher in non-rejecting mares than rejecting mares at day 1 post-partum.•The oestradiol to progesterone ratio increased from days 1 to 3 post-partum in mares that rejected foals.