NONINVASIVE HORMONE MONITORING IN CHINCHILLA:

BUSSO JM; PONZIO MF; FIOL DE CUNEO MH; RUIZ RD

Jornada; 2da Reunión Conjunta de Sociedades de Biología de la República Argentina.; 2011

Whether the steroid hormone is primarily passed into urine or feces is species-dependent, and this information is useful to a precise endocrine monitoring; in excretes metabolite concentrations are frequently several times higher than the concentration in blood. Wild Chinchilla lanigera is threatened (CITES I), although, domesticated form is widespread in breeding farms. Our experience on its reproductive endocrinology rises from radioinfusion studies of testosterone (in males), estradiol, progesterone (in females) and corticosterone (in both sexes). Testosterone, estradiol and corticosterone metabolites were excreted mainly by urine (84.7±4.2%, 71.7±12.1%, 86.9±0.07% respectively), while progesterone was detected in equal amounts of both excretes. Therefore, we proposed that the urinary route is preferential in Hystricognathi (chinchilla and guinea pigs; currently considered cavy-like forms) while in the Sciurognathi (squirrel and mouse-like forms, formerly considered Sciumorpha or Myormorpha suborders). This hypothesis was tested by matching our results and those reported for other rodents subjected to radiolabeled infusions. We consider that this proposal is relevant when the endocrine studies are faced in a new species