The work authorized by section 4:16-18 of this title, shall be done under the supervision of the poultry husbandman as head of the department of poultry husbandry. The experiment station may employ a trained poultry pathologist and, if necessary, a laboratory assistant. The poultry pathologist shall become a member of the staff of the department and shall devote his entire time to the work authorized by said section 4:16-18