Nest Building Behavior as an Early Indicator of Behavioral Deficits in Mice

Abstract

Nest building is an innate behavior in male and female rodents, even when raised in laboratory settings. As such, many researchers provide rodents synthetic and/or natural materials (such as twine, tissue, cotton, paper, and hay) as a gauge of their overall well-being and as an ancillary assessment to predict the possible decline in cognition. Typically, changes in nesting behaviors, such as failure to create a nest, indicate a change in health or welfare. In addition, nesting behavior is sensitive to many environmental and physiological challenges, as well as many genetic mutations underlying pathological disease states. The following protocol describes a nesting behavior paradigm that explores the usage of four types of nesting material. In addition, the protocol utilizes intraclass correlations to demonstrate that inter-rater reliability is higher when nests are constructed out of shredded paper compared to other common nesting materials such as cotton squares, paper twists, and soft cob bedding. The chosen methodology and statistical considerations (i.e., intraclass correlation) for this assay may be of interest for those conducting experiments assessing the quality of living of mice.

Digging behavior discrimination test to probe burrowing and exploratory digging in male and female mice

“…Mice would remove large portions of bedding from the burrow and start dispersing it in a thin layer in concentric circles on the surface of the corncob bedding. This behavior appears opposite to nest building behavior where soft substrate is accumulated (Deacon, 2012;Neely et al, 2019).…”

Chronic Mild Unpredictable Stress and High-Fat Diet Given during Adolescence Impact Both Cognitive and Noncognitive Behaviors in Young Adult Mice

“…Estep et al (1975) [ 83 ] used unbleached cotton batting, Torres-Lista & Giménez-Llort (2013) [ 77 ] compared paper towel and cotton, while Xiong et al (2018) [ 82 ] used white paper (similar to the current experiment). Neely et al (2019) [ 50 ] has shown that the type of material used to evaluate nesting can give different responses by raters that are blind to experimental condition, with higher average nest scores being given to mice using shredded paper (as done here and in previous research [ 57 , 79 ]) as compared to cotton squares, bedding, and paper twists. Shredded paper has also been shown to lead to more consistent results [ 50 ].…”

“…Neely et al (2019) [ 50 ] has shown that the type of material used to evaluate nesting can give different responses by raters that are blind to experimental condition, with higher average nest scores being given to mice using shredded paper (as done here and in previous research [ 57 , 79 ]) as compared to cotton squares, bedding, and paper twists. Shredded paper has also been shown to lead to more consistent results [ 50 ].…”

“…The type of nesting material should also be considered, as discussed by Neely et al (2019) [ 50 ]. In the analysis of nest building, researchers may use different materials.…”

“…Fresh bedding was placed in each individual shoe box cage and 3 g of shredded white paper was scattered in the cage. Shredded paper was used, since nests constructed out of this material have been shown to have higher inter-rater reliability among raters blind to experimental conditions when compared to other materials, including cotton squares or paper twists [ 50 ]. After 24 h, the nests were photographed and rated by trained raters blind to experimental condition on a scale of 1–5: 1 represented that no nest was constructed while a 5 represented a full nest had been constructed.…”