In the past 30 years, there have been decided increases in the reproductive efficiency of turkeys. Refinements in artificial insemination techniques have eliminated problems associated with natural mating, such as injury to the hen, clumsiness of the male, and preferential mating. Specially formulated diluents have made it possible to extend the semen from superior toms and reduce costs associated with maintaining large numbers of males. However, the turkey breeder hen still does not produce fertile eggs at the same level or with the same persistency as the chicken breeder hen.