“This is always a difficult time of year in the AFL landscape as the rules state we must make changes to our playing list,” Crows Senior Coach Don Pyke.
“Both Luke and Keenan have had a positive influence on our environment and can be proud of the way they have carried themselves.
“We wish them all the very best for the future.”
Lowden did not a play senior games for the Crows, after joining Adelaide at the end of 2014, following one game at the Hawks in five seasons.
Ramsey, selected with pick No.27 in the 2014 rookie draft also did not play a senior AFL match for Adelaide.