All baby chicks or turkey poults and hatching eggs sold or offered for sale by public hatcheries and chick dealers or jobbers as a regular part of their business shall originate in flocks that meet the requirements of the national poultry improvement plan as administered by the Alabama Department of Agriculture and Industries and the regulations issued by authority of this article for the control of pullorum disease; provided, that nothing in this article shall require any hatchery to adopt the national poultry improvement plan.