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There are 39 species in the Felidae family, the majority of which are facing declining populations in the wild due to habitat fragmentation and loss. Eighteen Felidae species are currently classified as Vulnerable or Endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, highlighting the need for ex situ conservation efforts for these animals. For institutions accredited by the Association of Zoos and Aquariums (AZA), these conservation efforts are a priority, helping to maintain populations of 14 imperiled wild cat species, as well as other felids facing population decline. Zoo-managed cats serve as assurance populations, ensuring that felid species are protected from extinction as wild populations continue to decline and potentially allowing for future reintroduction of zoo-born animals back into the wild.

Within AZA-accredited zoos, the Felid Taxon Advisory Group (TAG) is responsible for the management of all non-domestic cats within formal breeding programs called Species Survival Plans (SSPs). Zoo populations must be healthy, genetically diverse, and demographically stable to be sustainable, requiring collaboration for research, husbandry, veterinary care, and breeding. Preserving genetic variation is of particular importance, as many species are experiencing rapid loss of variation, which can lead to issues such as demographic bottlenecks, inbreeding depression, and founder effects. Felid TAG SSP program coordinators work with population geneticists from the AZA’s Population Management Center (PMC) to analyze pedigrees and make breeding recommendations for zoo-housed cats to limit the decline of genetic diversity over time. Selection for breeding is based on population biology and an overall relatedness factor known as mean kinship. The PMC also plays a vital role in matchmaking by identifying individual animals that are genetically underrepresented in the population so they can be prioritized for breeding plans.

It is important to note that SSP programs can only succeed if the animals are able to reproduce. Cats can display strong mate preferences, so a perfect genetic match may fail to breed due to behavioral incompatibility, aggression, or sexual disinterest. Estrus is difficult to detect in cats, and behavioral incompatibilities can increase when a matched pair is introduced during the wrong stage of the female’s estrous cycle. “Each breeding attempt involves detailed planning, knowledge of individual and species-level behavior, optimal husbandry, veterinary expertise, and, sometimes, ART [assisted reproductive technology] interventions like hormone monitoring or artificial insemination” says Dr. Lindsey Vansandt, director of the Imperiled Cat Signature Project at Cincinnati Zoo’s Center for Conservation and Research of Endangered Wildlife (CREW). There is now a growing understanding across zoos and aquariums that assisted reproductive technologies (ART) are needed for genetic and population management and long-term sustainability of imperiled felid species.

The application of ART addresses breeding challenges and enables us to matchmake pairs that otherwise would not be able to successfully reproduce. Each cat species presents unique challenges related to their reproductive biology, and because of these specificities there is no standard ART strategy that is applicable to all felids. Through previous and current research, a fundamental understanding of the reproductive physiology of each felid species is being developed to tailor ART on a species-by-species basis. CREW’s Imperiled Cat Signature Project team has pioneered methodologies to improve semen collection, handling, and cryopreservation, ovarian synchronization, and artificial insemination (AI).

Once a breeding pair is matched, rather than transporting animals between zoos, CREW’s scientists can travel to the zoo housing the male to perform a semen collection and freeze the semen in liquid nitrogen for the CryoBioBank. Semen cryopreservation ensures genetic diversity is not lost if an animal does not successfully breed naturally. Using frozen semen also extends the reproductive timeline, staying frozen for days, months, or even years until it is needed for a procedure. At the time of an AI procedure the frozen semen is transported to the zoo housing the female, thawed, and placed in her reproductive tract.

CREW has made multiple refinements to AI approaches in felids, including changes in the site of insemination and improved control of ovarian function. These advances have led to pregnancies in the ocelot, sand cat, fishing cat, Pallas’ cat, tiger, and jaguar. This includes a landmark achievement: the first jaguar cub ever born from any form of assisted reproduction. These refined techniques have also been successfully adopted by collaborators across the global zoo community, contributing to pregnancies in additional species such as the clouded leopard and Tsushima leopard cat. These outcomes highlight the growing capacity of institutions worldwide to implement ART in support of population sustainability.

These pregnancies are just the beginning, though. For ART to be consistently used as a population management tool, efficiency of AI protocols and ability to synchronize them with each female’s natural reproductive cycle must further improve, something that CREW is focusing on in their research.  “At the end of the day,” says Dr. Vansandt, “every cub born is the product of strategy, science, and dedication—and represents a small but mighty win for species survival.”