Each employee of the division who is responsible for the investigation or family assessment of reports of suspected child abuse or neglect shall receive not less than forty hours of preservice training on the identification and treatment of child abuse and neglect. In addition to such preservice training such employee shall also receive not less than twenty hours of in-service training each year on the subject of the identification and treatment of child abuse and neglect. Such annual training shall include at least four hours of medical forensics relating to child abuse and neglect as approved by the SAFE CARE network described in section 334.950.