Every fence shall be deemed a lawful fence as to any domesticated livestock that could not creep through such fence, if it is:
A cattle guard reasonably sufficient to turn all kinds of livestock shall also be deemed a lawful fence as to any domesticated livestock.
Nothing contained in this section shall affect the right of any such town to regulate or forbid the running at large of cattle and other domestic animals within its corporate limits.
The Board of Agriculture and Consumer Services may adopt regulations regarding lawful fencing consistent with this section to provide greater specificity as to the requirements of lawful fencing. The absence of any such regulation shall not affect the validity or applicability of this section as it relates to what constitutes lawful fencing.
Va. Code § 55.1-2804