(1) All persons receiving or purchasing milk or cream and all persons collecting milk or cream on milk and cream routes shall provide a licensed grader, weigher and sampler at each receiving station or for each route. All milk or cream purchased for use in milk plants or to be used in any manufactured dairy product in Montana must be graded by licensed graders, weighers and samplers. It is unlawful for any person to grade, weigh or sample any milk or cream to be used for processing into Grade A milk and cream or used in manufactured dairy products without first procuring a license as a grader, weigher and sampler from the department of livestock.