Reproductive and hormonal changes during the estrous cycle and pregnancy in Asian elephants (Elephas maximus)

Abstract 10.1002/zoo.1430090602.abs Serum progesterone and urinary total estrogen concentrations were determined weekly to bi-weekly in 2 female Asian elephants for 96 weeks. The mean estrous interval was approximately 16 weeks in the nonpregnant animal. A total of 5 cycles were observed in the 96 week study period. The serum progesterone concentration ranged from 150 pg/ml […]