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Paper towel shredding as a novel, affordable, noninvasive method for detecting arousals in hibernating rodents


Many research groups explore the regulation of hibernation or compare the physiology of heterothermic mammals between the torpid and aroused, euthermic states. Current methods for monitoring torpor (for example, infrared cameras, body temperature or heart-rate telemetry, and motion sensing) are costly, require specialized techniques, and can be invasive. Here we present an alternate method for determining torpor-bout duration that is cost-effective, noninvasive and accurate: paper towel shredding. In the winter, euthermic thirteen-lined ground squirrels will shred paper towels placed in the cage, but torpid animals will not. The presence of a shredded paper towel, indicating an arousal from torpor, is easily evaluated during routine daily monitoring. In 12 animals over 52 days, this simple technique detected 59 arousals with 100% accuracy when compared with the body temperature telemetry of the same animals. Moreover, this novel method avoids some of the drawbacks of other cheap monitoring systems such as the sawdust technique.

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Fig. 1: TBD.
Fig. 2: Arousals correspond with towel shredding.

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Data availability

Data are available via Figshare at (ref. 32) and (ref. 33). Source data are provided with this paper.


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The authors thank S. Thompson for animal management and C. Barghout for her help with animal care and paper towel recording. Funding for this project was secured by an NSERC discovery grant held by J.F.S.

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Authors and Affiliations



A.J.H. designed the experiment, captured animals, recorded paper towel shredding data and wrote the manuscript. B.M.D. captured animals, performed surgeries, set up the transmitter system, performed animal care duties and recorded paper towel shredding. L.H.R. helped with surgeries, performed animal care duties and recorded paper towel shredding. J.F.S. captured animals, edited the manuscript and secured funding for the research.

Corresponding author

Correspondence to Amalie J. Hutchinson.

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The authors declare no competing interests.

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Lab Animal thanks Dana Merriman and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

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Supplementary Fig. 1 and Table 1.

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Source data

Source Data Fig. 1

Raw data used to generate TBD figure.

Source Data Fig. 2

Raw data used to generate the body temperature aligned with towel shredding figure.

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Hutchinson, A.J., Duffy, B.M., Rego, L.H. et al. Paper towel shredding as a novel, affordable, noninvasive method for detecting arousals in hibernating rodents. Lab Anim 53, 117–120 (2024).

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