MEMPHIS, TENN - Memphis Zoo's Conservation and Research Department has conducted the very first study on reproduction technologies in the Rhaebo genus of toads.
The study was performed on the smooth-sided toad (Rhaebo guttatus), which is currently not considered vulnerable or endangered. However, of the thirteen species of toads in the Rhaebo genus, two are considered endangered: The Blue-spotted Toad (Rhaebo caeruleostictus) and the Carchi Andes Toad (Rhaebo colomai).
Memphis Zoo hopes this new research will eventually aid in the reproduction of these endangered species.
Memphis Zoo's research team approached this study with three main factors in mind: Could they increase the quality of sperm in the toads using hormones, could they successfully harvest the sperm from the toads, and could they freeze the sperm and measure the success rate? The answer to all three is yes.
Researchers tested two different types of hormones at three different concentrations to find the best method.
Memphis Zoo's Research team determined that a higher amount of one hormone performed better than the other hormone. They also had to determine the best time to collect sperm, which was found to be between two to five hours after administering the hormones.
Memphis Zoo's Research department was then able to determine toad sperm viability after harvesting the sperm and freezing them through a process called cryopreservation. After freezing the sperm, around 33% were observed moving and had the potential to fertilize.
Kristin M. Hinkson, J. Alex Baecher and Dr. Sinlan Poo, all part of the Zoo's Conservation and Research Department led by Dr. Steve Reichling, were involved in the research.
As amphibian species populations around the world decline, there is a growing interest of in vitro fertilization and lab reproductive technologies with these species.
Memphis Zoo is proud to be a leader in amphibian reproductive research and be an active contributor to conservation efforts around the globe.