Happy International Tiger Day. This day was created to help raise awareness for the largest living cat species on Earth. Although tigers once dominated the Asian landscape, habitat loss and poaching have dramatically decreased their populations, and today fewer than 3,500 tigers remain in the wild. Zoos across North America are mobilizing to raise awareness about wild tigers and support critical conservation efforts.
As part of the network of zoos accredited by the Association of Zoos and Aquariums (AZA), Cincinnati Zoo & Botanical Garden is fighting to secure the future of tigers. Within our AZA-accredited zoos, the Felid Taxon Advisory Group is responsible for the management of all non-domestic felids with formal breeding programs called Species Survival Plans (SSPs). Following a breeding recommendation from the Tiger SSP, Cincinnati Zoo made a love connection between our Malayan tigers Jalil and Cinta, who produced three adorable tiger cub girls in 2017.
Research is another critical component to tiger conservation. At Cincinnati Zoo’s Lindner Center for Conservation and Research of Endangered Wildlife (CREW), researchers are Saving Species with Science. One of CREW’s goals is to help zoos become more effective at propagating cats under human care, improving natural breeding, and incorporating assisted reproduction when necessary. Team Cat recently received a prestigious National Leadership Grant from the Institute of Museum and Library Services. The project is focused on developing and improving assisted reproductive technologies in four priority big cat species, including the tiger.
Working in partnership with scientists at Omaha’s Henry Doorly Zoo and Aquarium, Drs. Lindsey Vansandt and Julie Barnes recently hit the road to start saving tigers with science!
Dr. Julie performs a reproductive exam for Diesel, a four-year-old Amur tiger male who lives at Lee G. Simmons Wildlife Safari Park.
The semen collection was a success! Dr. Julie was able to collect 300 million sperm from Diesel.
When a lot of sperm is available, transcervical artificial insemination can be performed. Here Dr. Julie slowly deposits Diesel’s sperm into the uterus of Amur tiger female, Vera.
Next, the team prepares Vera for a laparoscopic artificial insemination, a surgical method where sperm is placed directly in the oviducts (i.e., fallopian tubes). Did you know? Tigers are completely striped. Their stripe pattern matches up with their skin.
Dr. Julie uses ultrasound to assess Vera’s ovarian response to the hormone treatment while Dr. Lindsey prepares the surgical equipment. Hormone treatment began two months ago to prepare Vera for her artificial insemination.
Dr. Lindsey places a surgical drape over Vera to create a sterile field.
Dr. Lindsey examines Vera’s reproductive tract. The advantage to using laparoscopy is that only tiny “keyhole” incisions are needed. A scope is placed and attached to a camera, allowing the whole team to visualize Vera’s tract. Vera’s ovaries had a great response to the hormone treatment, as several ovulations can be seen (red blister-like structures on the surface of her ovaries).
Dr. Julie operates the camera while Dr. Lindsey positions the oviduct in the proper orientation for the artificial insemination.
Dr. Shelley from the Omaha Zoo deposits sperm into the oviduct.
Now we cross our fingers (and toe beans!) and wait to see if Vera is pregnant.