Veterinarians and animal care staff at the Smithsonian’s National Zoo conducted a series of artificial insemination procedures on Shanthi, a 34-year old Asian elephant, September 19, 20, 21 and 22 with sperm from elephants from the Fort Worth Zoo and Tulsa Zoo. A successful pregnancy would be an important milestone in the Zoo’s commitment to Asian elephant conservation.
Scientists will monitor the level of the hormone progesterone in Shanthi’s blood. If concentrations remain elevated past 10 weeks after insemination, it most likely would mean she is pregnant, which would be confirmed by an ultrasound. An Asian elephant’s gestation period ranges from 20 to 22 months.
Artificially inseminating an elephant is a challenging and difficult medical procedure. Essential factors for success include a healthy reproductive tract for the elephant. The semen used for the procedure must also be of good quality and needs to be placed correctly in the cervix and/or uterus. Finally, the artificial insemination must be timed properly: Elephants have two surges of luteinizing hormone in about a three-week period. Using blood samples, scientists are able to detect when the first surge occurs. The second luteinizing hormone surge, which induces ovulation, follows about 20 days later, and that is when the artificial insemination takes place.
Shanthi gave birth to Kandula in 2001. He was the fifth elephant in the world conceived by artificial insemination. Through past artificial insemination procedures performed with Shanthi, Zoo scientists collected information that led to a greater understanding of elephant reproduction. Zoo reproductive physiologist Janine Brown discovered that elephants have a double luteinizing hormone surge, which turned out to be vital for the proper timing of the artificial insemination.An elephant birth would bolster the decreasing population of Asian elephants in North America and is an important step toward creating a multigenerational herd at the Zoo. The Zoo opened the first phase of its new home for Asian elephants, Elephant Trails, earlier this month. The habitat, when complete in 2013, will have the capacity to accommodate a natural, matriarchal herd of elephants and individual bulls—between eight and 10 adult elephants and their young.
National Zoo scientists have studied Asian elephants in the wild for more than 40 years in an effort to prevent their extinction. About 30,000 to 40,000 Asian elephants remain in the wild today.