Digging in Mice: Marble Burying, Burrowing, and Direct Observation Reveal Changes in Mouse Behavior

Mice spontaneously dig in many substrates in the laboratory. This behavior comes from their ancestry in the wild, where they would forage for seeds, grain, insects, and other food to be found buried in the soil or leaf litter in their natural habitat. The most convenient and sensitive way of measuring digging in mice is the burrowing test. Mice are placed in individual cages, each fitted with a “burrow,” a tube filled with food pellets or other substances. The amount of substrate spontaneously dug out of the burrow after 2 h and subsequently overnight is measured. The test is extremely simple to run; the apparatus is inexpensive and readily constructed. It exploits a common natural rodent behavior, provides quantitative data under controlled laboratory conditions, and has proved extremely sensitive to prion disease, lipopolysaccharide administration, strain differences, and brain lesions. Other ways of measuring digging behavior include direct observation and the marble burying test; full details as to how to run these are also given in this chapter.