Ovarian Follicle Culture in the Dog and Cat

scientists holding first litter of IVF puppies

Scientists from the Smithsonian Conservation Biology Institute's Center for Species Survival (CSS) are working to save species by developing in vitro culture techniques to better understand the mechanisms controlling ovarian follicle development. As the first scientists to successfully use in vitro fertilization in domestic dogs, CSS scientists hope to apply these techniques to save vulnerable species, such as the maned wolf.

Within the ovary, there are hundreds of thousands of immature eggs (inside structures called "follicles") that are never ovulated or fertilized. The ability to grow these immature eggs into mature counterparts capable of being fertilized and developing into healthy embryos would have enormous benefit for rescuing and protecting genetic diversity in endangered species, especially if a female of a rare species dies or loses fertility before reaching sexual maturation/puberty. These techniques could also help preserve fertility in women.

Led by CSS researcher Nucharin Songsasen these studies advance knowledge of carnivore folliculogenesis that will lead to the development of novel reproductive tools to ensure that every valuable individual has the opportunity to reproduce and contribute its genes to the next generation, which in turn is critical to maintain the genetic diversity and viability of these endangered populations.

Smithsonian Conservation Biology Institute scientists have developed culture systems that sustain living cat and dog follicles for a short time in an incubator, and used these systems to study the mechanisms that control follicle survival. They also investigated the effect of reproductive hormones (follicle stimulating hormone and luteinizing hormone) on dog follicle growth. CSS scientists are now studying the influence of growth factors and changes in the physical and biochemical microenvironment on follicle growth.

Partners and Collaborators

Yue Li, University of Maryland
Carol L Keefer, University of Maryland
Alex J Travis, Cornell University
Kohei Yamamizu, Kyoto University
John Fisher, University of Maryland
Utkan Dermici, Stanford University


This work is supported by the National Center for Research Resources, a component of the National Institutes of Health (NIH), the Office of Research Infrastructure Programs/Office of the Director (NS), the Japanese Society for Promotion of Sciences (MF), the Baker Institute for Animal Health and the Atkinson Center for a Sustainable Future, Cornell University (JN) and the Smithsonian Institution.

photo: Jeffery MacMillan


Fujihara et al. 2014. Epidermal Growth Factor (EGF) Sustains In Vitro Primordial Follicle Viability by Enhancing Stromal Cell Proliferation via MAPK and PI3K Pathways in the Prepubertal, but Not Adult Cat Ovary, Biology of Reproduction, 90(4):86, 1-10. Fujihara et al, 2012. Cat and dog primordial follicles enclosed in ovarian cortex sustain viability after in vitro culture on agarose gel in a protein-free medium. Reprod Domest Anim, 47(6):102-108. Nagashima et al. 2015. Follicular size and stage and gonadotropin concentration affect alginate-encapsulated in vitro growth and survival of pre- and early antral dog follicles. Reprod Fertil Dev. Aug 3. Songsasen et al. 2012. The domestic dog and cat as models for understanding the regulation of ovarian follicle development in vitro. Reprod Domest Anim, 47(6):13-18. Songsasen et al. 2011. In vitro growth and steroidogenesis of dog follicles are influenced by the physical and hormonal microenvironment. Reproduction, 142:113-122.

Continue Exploring

Changing Landscapes Initiative

Smithsonian scientists work alongside community members in Northwestern Virginia to evaluate the impacts of land-use change on wildlife, ecosystem services and community health.

Coral Biobank Alliance

Smithsonian scientists are part of the Coral Biobank Alliance, a global network of coral experts preserving corals for restoration and research.

Coral Species Cryopreserved with Global Collaborators​

View a list of the coral species that have been cryopreserved using a technique developed by Smithsonian scientists.

Wildebeest Conservation

Conservation Ecology Center scientists are tracking the movements of white-bearded wildebeest to understand how changes across the landscape impact the species.

Protecting Piping Plovers in the Great Lakes

In 2022, the Smithsonian Migratory Bird Center will begin a new research project to help protect endangered piping plovers from predation by merlins.

Swift Fox Recovery

Smithsonian scientists, in collaboration with the Fort Belknap Fish and Wildlife Department, are embarking on a five-year swift fox reintroduction project to restore swift foxes to tribal lands and to help reestablish connectivity between disjointed swift fox populations.

Conserving the World’s Largest Working Wetland

Conservation Ecology Center researchers are collaborating with institutions in Brazil and other Smithsonian colleagues to support sustainable cattle ranching in the Pantanal wetland.