Reversible downregulation of endocrine and germinative testicular function (hormonal castration) in the dog with the GnRH-Agonist Azagly-Nafarelin as a removable implant “Gonazon”; a preclinical trial - Ludwig, C; Desmoulins, PO; Driancourt, MA; Goericke-Pesch, S; Hoffmann, B (Theriogenology, 2009)