(a) It shall be lawful in this state for any recognized poultry flock owners to buy and use sulfaguanidine and sulfathiazole in original packages in powdered form only for their own requirements in the treatment of poultry diseases. Dealers in poultry supplies may buy and sell sulfaguanidine and sulfathiazole.

(b) No person, firm, or corporation in this state shall sell or offer for sale sulfaguanidine or sulfathiazole unless each is plainly labeled with the words "For Poultry Only."