FREE MOVEMENT OF GOODS - DEROGATIONS - PROTECTION OF PUBLIC HEALTH - COMPOUND FEEDINGSTUFFS - MANUFACTURE AND MARKETING GOVERNED BY A COHERENT AND COMPLETE SET OF DIRECTIVES HARMONIZING NATIONAL LEGISLATION - UNILATERAL NATIONAL MEASURES - NOT PERMISSIBLE ( EEC TREATY , ARTS 30 AND 36 ; COUNCIL DIRECTIVES 70/524 , 74/63 AND 79/373 )