No person in buying or selling eggs shall take or give a greater or lesser dockage for eggs unfit for human food, as herein defined, than the actual dockage as determined by the correct candling of the eggs purchased or sold. No person in buying or selling eggs shall overgrade or undergrade eggs. All licensed persons shall keep such candling and grading records of eggs purchased or sold as may be required by the rules promulgated by the commissioner, which records shall be available at all reasonable times for inspection and examination by the commissioner, inspector or employees of the Department of Agriculture.