Some states are “open range” or a “fence out” states, meaning that a livestock owner does not have a legal duty to prevent animals from getting onto the roadway. But some state legislatures have enacted statutes known as "stock laws" that modify the common law (rules contained in court opinions written by judges) and prohibit owners from allowing animals to run at large.
Nevada is considered an 'open range' state, which traditionally means that livestock owners are not required to fence in their animals to prevent them from wandering onto roadways. However, the state has implemented certain 'stock laws' that modify this general rule. Under Nevada law, specifically NRS 569.431, certain areas can be designated as closed range by the board of county commissioners where livestock owners are required to prevent their animals from running at large, which includes straying onto highways. These areas are typically marked with signs indicating that it is unlawful for livestock to be at large. Outside of these designated areas, the open range law still applies, and motorists are expected to exercise caution to avoid collisions with animals.