 Interest in "L. reuteri" began to increase when scientists found it colonizing the intestines of healthy animals.Reuter first isolated "L. reuteri" from human fecal and intestinal samples in the 1960s.The same experiments – attempting to isolate "L. reuteri" from feces and intestine of healthy animals – were done on nonhuman species, demonstrating that "L. reuteri" seems to be present throughout the animal kingdom.