There shall be five delegates from this state to the compact commission, and these delegates shall be appointed by the commissioner of agriculture. At least one of the delegates shall be a dairy farmer who is engaged in the production of milk at the time of appointment or reappointment, at least one delegate shall be a consumer representative, one delegate shall be a processor, one delegate shall be a retailer representative from a border county and one delegate at large. Delegates shall serve for a term of four years. Vacancies in the state delegation will be filled in the same manner as the appointment of delegates, and shall be for the term of the position vacated.