Portable-size artificial uterine system for viviparous shark embryos.

In this study, we developed a portable artificial uterus specifically designed for viviparous elasmobranchs (sharks and batoids). This new method is different from the previous method owing to the absence of fluid-cleaning filters, a smaller amount of incubation fluid, and the use of a mini-sized refrigerator for temperature control. Due to these modifications, the total weight decreased to approximately 40 kg, which is less than one-twentieth that of the previous system. We confirmed that embryonic lanternsharks (Etmopterus molleri) survived in this system for over two months, demonstrating its efficacy. In addition to its primary use as an extra-uterine life support system for viviparous elasmobranch embryos in laboratory conditions, the new system can be used for the long-term transport of premature embryos, which was not feasible with previous systems.•A novel artificial uterine system for viviparous elasmobranchs was developed.•The new system is reduced in size to a portable level by simplifying the previous system.•This system can be used for long-term transport of prematurely born embryos.