The following link from the "Office of Environment and Rural and Marine Affairs" of the Embassy of Spain in Washington DC contains information on non-commercial importation of dogs, cats and ferrets from Canada to Spain:
http://www.magrama.gob.es/es/ministerio/funciones-estructura/organizacion-organismos/ministerio-exterior/consejerias/americadelnorte/eeuu-canada/importaciones/
The veterinary certificate mentioned on that web page must be signed by a licensed veterinarian and endorsed by an Official Veterian from the Canadian Food Inspection Agency(CFIA). You can find your local Canadian Food Inspection Agency Office at:
www.inspection.gc.ca