About the Lab & Staff

ZMDx logo

The ZMDx Laboratory’s beginnings can be traced back over two decades. In the early 2000’s, the lab started to take shape thanks to Dr. Elliot Jacobson, now a professor emeritus at UFCVM. Initial diagnostic offerings centered on ophidian paramyxovirus serology. However, thanks to the contributions and efforts of multiple talented clinicians, residents, and graduate students, including Dr. Jim Wellehan, Dr. April Johnson, Dr. Brian Stacy, Dr. Hendrik Nollens, and Dr. Francesco Origgi, the lab began to develop and offer a variety of PCR tests.

Yellow frog

Continued development and optimization of different PCR assays allowed the lab to grow into the molecular diagnostic laboratory as we know it today. Work done in the lab has been crucial in the identification and characterization of numerous infectious diseases of the utmost clinical significance to captive- and free-ranging wildlife, including intranuclear coccidiosis in tortoises, inclusion body disease in snakes, avian and non-avian reptile herpesviruses, nasal Helicobacter in tortoises, and serpentoviruses in snakes.

We are proud to have played a role in the diagnosis and characterization of so many diseases of the wildlife species that we cherish so highly. We plan to continue to make contributions that advance the state of the field, and we look forward to working with all of our clients to improve the health of captive and free-ranging wildlife.

Current Lab Members

Laboratory Manager

April Childress

April Childress has been a member of the ZMDx Lab before it was even officially a laboratory. She started in 2003 as a technician with Dr. Elliot Jacobson, assisting PhD students with their projects. In 2005, when the lab was formally established, she took on the role she maintains to this day as Lab Manager. She oversees all aspects of lab operations; she enjoys the challenges and rewards the ZMDx Lab offers, and finding novel pathogens is always a bonus.  April says, “if reincarnation is real, I hope to come back as an otter so I can play all day.”

April in the lab

laboratory technician

Sierra N Dos Santos

Sierra is the newest member of the ZMDx team, joining the lab in 2022 as a laboratory technician. Sierra graduated from the University of Florida with a BS in Microbiology in 2023. She has two cats named Jasper and Fiyero, one that’s a tuxedo and the other albino. But her favorite animal is a slightly bigger cat, the snow leopard. She fell in love with lab work and diagnostics while taking a microbiology class to originally become a veterinarian. Since then, she changed her career passion and plans on furthering her education to become a pathologist. Outside of work, she enjoys traveling, going to Disney, and playing board games with friends or family.

Sierra sitting in the woods

laboratory co-director

Dr. Jim F.X. Wellehan, Jr.

Jim is a Professor in the UFCVM, diplomate of both the American College of Zoological Medicine and the American College of Veterinary Microbiologists. Jim started developing molecular diagnostic tests in 2002 that would later become the basis of the ZMDx Laboratory. In addition to his role with the ZMDx Lab, he is a clinician with the UF Zoological Medicine Service and the veterinarian of record for Santa Fe Teaching Zoo and Lubee Bat Conservancy. He can generally be found in the zoo ward fixing owls and tortoises, and prattling on about dinosaurs, microbial ecology, and phylogenetic trees. His research interests focus on evolution and ecology of pathogens of nondomestic animals, with an emphasis on molecular diagnostics and pathogen discovery. Outside of work, he enjoys backpacking, mountain biking, and playing anything with strings and frets. He is happily married to Karen Schaedel and they are the proud parents of Xavier and Elseya. He would like to leave them a world with less racism, sexism, homophobia, and economic disparity that is working to mitigate the ongoing climate change crisis.

Dr. Wellehan with a hawk

laboratory co-director

Dr. Robert “Oz” Ossiboff

Oz is a Clinical Associate Professor in the UFCVM, and a diplomate of the American College of Veterinary Pathologists. He moved to Florida in 2017 following training and professional positions at Cornell University, the Wildlife Conservation Society (Bronx Zoo), and the Zoological Pathology Program at the University of Illinois Urbana-Champaign. In 2018, he became co-director of the ZMDx Lab alongside Dr. Wellehan, and works closely with April to oversee all aspects of lab function. In addition to his work with the ZMDx Lab, Oz is the director of the Aquatic, Amphibian, and Reptile Pathology Service at UFCVM. He is incredibly passionate about the health of reptiles and amphibians, and focuses his clinical and research efforts to advance the state of herpetological medicine and our knowledge of herp diseases. While Oz may admittedly work excessively at times, when not working he enjoys spending time with his family, practicing photography, and waiting for the cooler weather that Gainesville only sees for much too short of each year.

Dr. Ossiboff