specific pathogen free(redirected from Specified pathogen free)
specific pathogen free
a term applied to animals reared for experimentation or to commence new herds or flocks of disease-free animals; abbreviated SPF. Animals usually obtained as for axenic animals but are then placed into a nonsterile environment in which they become infected with a range of microorganisms, many colonizing as so-called normal flora. Certain defined specific pathogenic microorganisms are not present in the environment so that SPF animals can be stated to be free of infection or previous infection with the specified microorganism. See also gnotobiotic animal.