The county highway superintendent shall have control, government, and supervision of all the public roads and bridges in the county under the general supervision and control of the county board. Before entering upon the duties of his office he shall execute to the county a bond in the sum of five thousand dollars, to be approved by the county board, conditioned for the faithful performance of his duties, and to account for all funds and property that may come into his possession. The county highway superintendent shall prepare and file an annual inventory statement of county personal property in his custody or possession as provided in sections 23-346 to 23-350.