If numbers permit Open Mdn races for the next period of time may be split into a Mdn race for 3YOs only and a Mdn race for older horses. Three year old Mdn races are 57.5kg for males and 55.5kg for fillies. Currently, if a 3YO competes in an open Mdn race they a receive 2.5kg allowance prior to any sex allowance being applied.