1. Department of Animal Pathology, Veterinary Faculty, University of Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain
2. Hormonal Biochemistry Laboratory, Universitary Clinical Hospital, Avda. S. Juan Bosco 15, 50009 Zaragoza, Spain
3. Biochemistry Service, Miguel Servet Universitary Hospital, P° Isabel La Católica 1, 50009 Zaragoza, Spain