Establishment and characterisation of oviductal organoids from farm and companion animals

Organoid technology has provided us with a unique opportunity to study early human development and decipher various steps involved in the pathogenesis of human diseases. The technology is already used in clinics to improve human patient outcomes. However, limited knowledge of the methodologies required to establish organoid culture systems in domestic animals has slowed the advancement and application of organoid technology in veterinary medicine. Here, we have developed a platform to grow organoids from animal tissue samples and characterized oviductal organoids from five domestic animal species. Organoids were grown progressively from single cells derived from the enzymatic digestion of freshly collected equine, bovine, feline, canine, and porcine oviducts. The addition of WNT, TGFB, BMP, Rock, and Notch signalling pathway activators or inhibitors in the culture medium suggested remarkable conservation of the molecular signals involved in oviductal epithelial development and differentiation across species. The gross morphology of organoids from all the domestic species was initially similar. However, some differences in size, complexity, and growth rate were observed and described. Well-defined and synchronised motile ciliated cells were observed in differentiated organoids in mature populations. Histopathologically, oviductal organoids mimicked their respective native tissue. In summary, we have developed a detailed cross-species comparison of oviductal organoid models, which will be valuable for advancing assisted reproductive technologies and fertility studies in these animal species in the future.