Within six months after the lines of the railroad or any part thereof is open, each railroad shall erect and thereafter maintain fences on the sides of its right-of-way, or the part thereof so open for use, suitable and sufficient to prevent cattle, horses, sheep, and hogs from getting on such right-of-way, except at the crossings of public roads and highways, and within the limits of towns, cities, and villages, with openings, gates, or bars at all the farm crossings of its tracks for the use of the proprietors of the lands adjoining such right-of-way. Each railroad shall also construct and maintain, at all road crossings, cattle guards suitable and sufficient to prevent cattle, horses, sheep, and hogs from getting onto such right-of-way.