Reproductive activity after induced anestrus using altrenogest in iTursiops truncatus/i females in captivity in marine environment

Abstract

Interest to reproduce Bottlenose dolphin (Tursiops truncatus) in captivity has increased due to the international restrictions for its commercialization and the risks and logistical difficulties for transporting specimens. Therefore, it has become important to study its reproductive biology in captivity. The objective of the present study was to determine altrenogest (Regumate ®) post-treatment indicators of vaginal cytology, estradiol levels and restarting of reproductive activity of T truncatus females in captivity in marine environment. Twelve females received altrenogest at a daily dose of 0.07mg kg-1 for a year. A total 420 slides of vaginal cytology of each female were performed to determine the percentage of cornified cells. Also, 60 blood samples of each animal were analyzed to determine estradiol levels. Regarding the vaginal cytology; percentage of cornified cells increased between 60 and 70% from day 4 to day 9 after removing the altrenogest treatment and between 70 and 80% from day 12 to day 19. Estradiol levels were in the range of 16 to 1l4pg ml-1 during the entire monitoring period. A positive correlation (r = 0.7062; P0.05) was found between these indicators. Therefore, we conclude that treatment with altrenogest and monitoring the estrous cycle with simple techniques such as vaginal cytology might be used for designing protocols for assisted reproduction for groups of T truncatus in captivity.