The Commissioner shall annually cause to be analyzed at least one sample so taken of every commercial feed that is found, sold or offered or exposed for sale in this State under the provisions of Articles 1 to 9 of this chapter. The samples, not less than one pound in weight, shall be taken from not less than ten bags or packages, or if there be less than ten bags or packages, then from each bag or package, if it be in bag or package form, or if such commercial feed be in bulk, then from ten different places of the lot.