First report on the colpocytology and serum steroid hormone levels of Giant otters Pteronura brasiliensis

Abstract

Considering the importance of tools for the reproductive monitoring and management of Giant otters Pteronura brasiliensis in the wild or in captivity, this study reports the relationship among the colpocytology, reproductive serum hormone (progesterone and oestradiol) levels and ovarian morphology of adult Giant otters. Blood and vaginal cytology samples were obtained from four adult females (two free-ranging and two in human care). The ovaries were collected from the captive females. The data were correlated to define the phase of the oestrous cycle of each animal. The results suggest the feasibility of using hormone analysis or colpocytology to aid in the reproductive monitoring of Giant otters in human care. In addition, these tools could be used to define the reproductive status of individual wild Giant otters during capture procedures.