[Reproductive physiology of the European mink: progesterone profile during pregnancy]

Reproductive physiology of the European mink, an endangered mustelid species, has been so far scarcely investigated. This study confirms that in European mink embryo implantation occurs on the day 12 of pregnancy. Progesterone profile during pregnancy has been compared in European mink and domestic ferret. In both species, progesterone increases at peri-implantation period, i. e. on day 8 and day 12 after mating. However, toward the end of pregnancy, on day 40 after mating, progesterone concentration in faeces of the ferrets decreases and does not differ from the initial level. In contrast, increase of progesterone during first 12 days of pregnancy in European mink is not as rapid as in ferrets, but in this species, there is no visible decrease of progesterone at the end of pregnancy. Peak levels of progesterone in faeces (day 8, 12) are lower in European mink than in ferret.