It shall be unlawful for any person, firm, corporation or association to sell or offer for sale, distribute, administer, barter, exchange, give away or otherwise dispose of unattenuated hog cholera virus except upon a special written permit issued by the commissioner of agriculture.
"Hog cholera virus" means an unattenuated virus administered to swine for the purpose of immunizing such swine against the disease known as hog cholera.