We are planning on retaining all of our heifer calves this year and was wondering about implanting them once in the spring. If any of you do this and if so what implant do you use. My man cub is 16 this year and has aspiration's of ranching after high school and I'll do my part to help him. He has his sheep flock plus a dozen cows and relief milks for two dairy farms so he know's what work is.