INSTITUTO DE INVESTIGACIONES EN CIENCIAS DE LA SALUD
Unidad Ejecutora - UE
Evaluation of three immunoassay systems for the assessment of urinary biomarkers of ovarian function in the endangered chinchilla (Chinchilla lanigera).
PONZIO M.F.,; MASTROMONACO G; GALEANO M.G.; GILMAN C; RUIZ R.D,; FIOL DE CUNEO M
WIENER TIERARZTLICHE MONATSSCHRIFT
B W K PUBLISHING SOLUTIONS & VERLAG
Lugar: Vienna; Año: 2012 vol. 1 p. 46 - 46
Intensive hunting for fur placed chinchilla populations at the brink of extinction (IUCN critically endangered - Appendix I of CITES). Although native chinchilla are extremely rare, a hybrid has been bred for fur production, providing a unique model to develop procedures that could be applied to their endangered counterparts. Despite its biological and economic importance, little scientific information is available about this species? basic reproductive physiology, a key aspect for the implementation of captive breeding programs. Attempts to obtain repeated blood samples from chinchillas were unsuccessful because of their stress-susceptible nature. Therefore, non-invasive techniques provided a unique opportunity, allowing long-term endocrine monitoring while avoiding the stress-evoking stimuli of restraint and repeated venipuncture. The objective of the present study was to test the validity and accuracy of different assays systems for the quantification of urinary biomarkers of ovarian activity in the chinchilla. Urinary steroid metabolites were assessed in 24 h urine longitudinal samples before and after the injection of eCG alone (Novormon, Syntex, 30 I.U., n=6). Hormone assays tested included creatinine (colorimetric assay from creatinine standard set, Sigma #C3613), pregnanediol glucuronide (PdG, C. Munro R13904) and estrone conjugate (EC, C. Munro R522-2) by EIA. Comparative profiles of progesterone (P) and estradiol (E) metabolites using RIA were also determined (I125 RIA kits, Coat-A-Count, Siemens). Finally, the same samples were quantified for 17â-estradiol and progesterone metabolites using an electrochemiluminescence immunoassay (Roche Diagnostics). After eCG injection, elevation of urinary PdG and EC metabolites above baseline levels occurred after 7 and 9 days respectively, reaching values of 2720 ± 1109.8 and 22.5 ± 9.7 ng/mg creatinine. Similar profiles were obtained using both assays for E and P determinations, yet metabolite concentrations were significantly lower. An improved understanding of these aspects will undoubtedly help researchers to use more effective assay systems for the evaluation of reproductive function in this species.