The commissioner shall, with the approval of the State Board of Agriculture and Industries and as otherwise provided by law, appoint such chiefs, assistants, deputies, agents, experts and other employees as are necessary for the successful administration of the affairs of the department and prescribe their duties. The chief clerk of the commissioner shall, before entering upon the duties of his office, execute to the State of Alabama a bond, to be approved by the Governor, in the amount of $10,000.00, for the faithful performance of his duties. Other employees shall execute to the state such official bonds as the commissioner may determine and require, unless otherwise expressly provided by law.