A certificate, when not superseded by a finding of the grade or other classification of any farm product issued under this act, and a certificate issued by the United States Department of Agriculture, independently or in co-operation with a co-operating agency, as to grade or other classification of any farm product, when certified by the authorized agent of that department, shall be accepted in any court of this Commonwealth as prima facie evidence of the truth of the statements therein contained, including the true grade or other classification of such farm product at the time of its classification.
3 P.S. § 25