Noninvasive monitoring of female reproductive hormone metabolites in the endangered European mink (Mustela lutreola).
This study examined the reproductive physiology of female European mink (Mustela lutreola) to augment the available information on estrus, ovulation, and pregnancy with the long-term goal of supporting ex situ breeding management of this highly endangered species. Fecal reproductive hormone metabolites were measured using EIAs for estrogen and 20-oxo-pregnane metabolites. Seasonal hormone profiles were established. A comparison of hormone fluctuations in pregnant and nonpregnant females showed that both estrogen and 20-oxo-pregnane metabolites were significantly elevated during gestation, which is 42 days in length. Delayed implantation or embryonic diapause does not occur in this species. Litter size was correlated with 20-oxo-pregnane levels but not with estrogen concentrations. During lactation, 20-oxo-pregnane metabolite levels remained higher than in nonpregnant females. The breeding season was characterized by peaks in vaginal cornified cells and fecal estrogen metabolite levels. Up to four peaks in estrogen levels were identified and confirmed that European mink are seasonally polyestrous. The results of 20-oxo-pregnane measurements indicated that hCG can be applied to induce ovulation. With the establishment of this noninvasive method, we present a new tool to support population management of this species.
Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine, Vienna, Austria.
Astrid
A
Nagl
Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine, Vienna, Austria.
Nadja
N
Kneidinger
Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Tartu, Estonia.
Kairi
K
Kiik
Natural Resources Institute Finland, Green Technology, Maaninka, Finland.
Heli
H
Lindeberg
Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Tartu, Estonia; Species Conservation Lab, Tallinn Zoological Gardens, Tallinn, Estonia.
Tiit
T
Maran
Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine, Vienna, Austria. Electronic address: Franz.Schwarzenberger@vetmeduni.ac.at.
Franz
F
Schwarzenberger
D000818:Animals; D004967:Estrogens / Q000737:chemistry* / Q000378:metabolism; D005243:Feces / Q000737:chemistry*; D005260:Female; D008907:Mink / Q000502:physiology*; D011247:Pregnancy; D011278:Pregnanes / Q000737:chemistry* / Q000378:metabolism; D012098:Reproduction / Q000502:physiology; D012621:Seasons; D013997:Time Factors
C523861:20-oxo-pregnane; D004967:Estrogens; D011278:Pregnanes
Captive management; Estrogen; Induced ovulation; Pregnane; Progesterone metabolite; Species conservation