germ-free animal


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germ-free animal

a laboratory animal raised under sterile conditions, free of exposure to microorganisms. The diet is controlled, preventing exposure to microorganisms that may be in food. The germ-free animals have lymphoid tissue that is not fully developed and may have a deficiency of serum immunoglobulin.
References in periodicals archive ?
The sterile environment allows researchers to compare germ-free animals with those raised normally.
Germ-free animals have extensive deficits in the development of the gut-associated lymphoid tissues (GALT) and defects in antibody production.
These germ-free animals are leaner than animals that are colonized with a complex microbial community, even though they eat more food," says Peter Turnbaugh of Harvard University's FAS Center for Systems Biology.