Any mammal can lactate with the right amount of hormones and development. So in short answer to your question, yes, it is quite possible for shemales (men) to lactate if given the correct dose or estrogen, progestin, and/or estradiol for an extended period of time and then given the hormone Prolactin and oxytosin. Even you could lactate if given this hormone regiment. This is not to say ALL shameles can lactate because many breast implants will destroy the milk ducts.