Eco-ultrafiltrates (EUF) are cell extracts from fetal organs or tissues of low molecular weight as determined by the size of the micro pores in the ultrafilter.

Eco-ultrafiltrates (EUF) of organs and tissues are obtained from fetal organs or tissues from closed colony of rabbits or other animals as per requirement of U.S. FDA (U.S Food and Drug Administration), WHO (World Health Organization) and AAALAC (Association for Assessment and Accreditation of Laboratory Animal Care International).