With a history of verified results from collaborative research, CREW scientists understand the importance of developing
scientific capacity within individuals and organizations throughout North America to overcome the serious loss of
genetic diversity facing captive African and Asian rhino populations.
In the first year of a three-year National Leadership Grant from the Institute of Museum and Library Services (IMLS), CREW
has begun building a Rhino Assisted Reproduction Enterprise (RARE) in collaboration with SeaWorld Busch Gardens Reproductive Research Center and several other zoos accredited by the Association of Zoos & Aquariums. These zoos contribute the veterinary and rhino keeper staff time needed to learn and implement rhino assisted reproductive techniques,
with the necessary training, tools and laboratory support provided by CREW.
One objective of the grant is to contribute to the genetic management and propagation of captive Indian rhinos through artificial insemination (AI). Although AI in Indian rhinos is still a work in progress, the achievements made during CREW’s initial 8-year effort are impressive with six conceptions and four term calves produced. Because there is a steep learning curve to these procedures, we are hopeful that success will become even more common over time. Participating zoos agree to collect and ship rhino urine samples on a frequent basis to CREW for hormone analysis needed to time AI. Rhino keeper staff at each facility condition females to enter a chute for the purpose of performing AI and the standing sedation protocol already established for successful intrauterine AI in this species is implemented prior to expected ovulation date. Each facility observes one AI before performing the next AI under CREW supervision.
We are happy to report that the Denver Zoo team is now fully trained in Indian rhino AI and is performing procedures in house using sperm from CREW’s CryoBioBank. Our long-term commitment to rhino conservation has positioned us to respond to the growing need of zoos to build their capacity for assisted reproductive technology for rhinos. We are gladly meeting this challenge and enjoying establishing a network of RARE researchers united for a common cause – to save rhinos. A RARE endeavor indeed.
February 8, 2016 2 Comments
Glass Glass Baby: Birth of Healthy Kittens following Sperm Vitrification for Artificial Insemination
A world leader in small cat reproductive research, our Center for Conservation and Research of Endangered Wildlife (CREW) has successfully produced the first non-human offspring – two kittens – using vitrified sperm (semen preserved as glass instead of ice) for artificial insemination (AI). Dr. Bill Swanson explains the significance of this breakthrough in this video.
Cryopreservation of cat semen for assisted reproduction can be challenging, requiring technical expertise and specialized equipment for semen collection, processing and freezing. As a simplified alternative to standard semen cryopreservation methods, CREW scientists have been investigating the use of vitrification – the ultra-rapid cooling of liquids to form a solid without ice crystal formation. This approach essentially preserves semen as glass instead of ice.
For vitrification, cat semen is diluted in a chemically-defined medium containing soy lecithin and sucrose as cryoprotectants and, after a five minute equilibration period, pipetted in small volumes (~30 microliters) directly into liquid nitrogen to form tiny glass marbles of frozen sperm.
In initial studies, we found that cat sperm survived vitrification as successfully as that frozen using standard straw freezing methods and that vitrified sperm were capable of fertilizing cat oocytes in vitro. In our first assessment of in vivo viability, eight of these embryos were transferred into three synchronized females. Although one female appeared to have two early implantations, no offspring were produced.
In a follow-up study, artificial insemination (AI) with vitrified sperm was assessed in three additional females. With our laparoscopic oviductal AI technique (LO-AI), only a couple million sperm are required per insemination, allowing the use of the relatively low sperm numbers that are preserved in vitrified semen pellets. Following LO-AI with vitrified sperm, all three females conceived, with two of the pregnancies progressing to term and culminating in the birth of two healthy kittens in early April. These kittens, a male named Vito (short for vitrification) and a female named Elsa (after the character in the movie Frozen), are the first non-human offspring – of any species – produced with vitrified sperm (although three human babies have been born from earlier research).
Our preliminary results with semen from fishing cats and ocelots indicate that vitrification is effective for preserving post-thaw sperm viability and function across cat species. These findings suggest that this fast and simple cryopreservation method may have broad applicability for semen banking of endangered felids housed in zoos and possibly living in the wild.
The study’s lead author, veterinary student Jaci Johnson, has been selected to present these findings at the upcoming American Association of Zoo Veterinarian’s Annual Meeting in Portland, Oregon. (Funded, in part, by the Procter & Gamble Wildlife Conservation Scholarship program in collaboration with Ohio State University’s College of Veterinary Medicine.)
- Reprinted from the Spring 2015 CREW Progress Report
May 14, 2015 1 Comment
You probably already know that the Cincinnati Zoo is committed to the conservation of lions, tigers and cheetahs, but did you know that we are also leading the way in small cat conservation? And our Small Cat Signature Project just got bigger! Our Center for Conservation and Research of Endangered Wildlife (CREW) recently received a Museums for America Grant from the Institute of Museum and Library Services to improve our ability to maintain healthy captive populations of five small cat species across the country—the Brazilian ocelot, the Pallas’ cat, the black-footed cat, the Arabian sand cat and the fishing cat.
Unfortunately, none of these small cat populations are considered sustainable through natural breeding alone. That’s where Dr. Bill Swanson, CREW’s Director of Animal Research and the world’s leading expert on small cat reproduction, comes in. Working in partnership with Dr. Jason Herrick of the National Foundation for Fertility Research and the Species Survival Plan coordinators for each species, Dr. Swanson will direct the project with a focus on three goals: 1) Collect and freeze semen from the most valuable cats for each species, 2) Produce viable offspring using artificial insemination in recommended breeding pairs that fail to reproduce naturally, 3) Produce offspring with frozen-thawed semen from genetically valuable or under-represented males.
Building on CREW’s decades of ground-breaking research on small cat reproduction, successful completion of this project will greatly enhance the sustainability and stewardship of small cat collections in AZA zoos. Now that’s big news!
October 9, 2014 1 Comment