title: Pathogen-free substrates for gerontologic research: review, sources, and comparison of barrier-sustained vs conventional laboratory rats.
mesh_terms: D000375:Aging; D000818:Animals; D000830:Animals, Laboratory; D001947:Breeding; D004195:Disease Models, Animal; D004995:Ethics, Professional; D005856:Germ-Free Life; D007239:Infections / Q000662:veterinary; D011786:Quality Control; D051381:Rats; D011919:Rats, Inbred Strains; D012106:Research; D012376:Rodent Diseases / Q000517:prevention & control