Data from: Individual differences in torpor expression in adult mice are related to relative birth weight
Data files
Apr 16, 2018 version files 1.91 MB
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Kato et al_bodytemperature.xlsx
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Kato et al_bodyweight.xlsx
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Kato et al_Fig1.xlsx
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Kato et al_Fig2.xlsx
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Kato et al_Fig3.xlsx
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Kato et al_Fig4.xlsx
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Kato et al_FigS1.xlsx
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Kato et al_FigS2.xlsx
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Kato et al_FigS3.xlsx
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Kato et al_glmer analysis.xlsx
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Kato et al_logger weight.xlsx
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Kato et al_torpor bout length.xlsx
Abstract
Daily torpor is a physiological adaptation in small mammals and birds, characterised by drastic reductions in metabolism and body temperature. Energy-constraining conditions, such as cold and starvation, are known to cause the expression of daily torpor. However, the reason for high degrees of inter- and intra- individual variation in torpor expression (TE) in similar situations is not clear. As littermates of altricial animals are exposed to an uneven allocation of maternal resources from conception to weaning, we tested whether early nutritional experiences have long-term effects on TE in adults. We used full-sibling littermates of laboratory mice that as adults were starved overnight to induce torpor. We measured body weight from birth until adulthood as an indicator of nutritional status, and calculated the relative body weight (RBW) as an indicator of the difference in nutritional status within a litter. After maturation, we subjected mice to five repeated torpor induction trials involving 24 hours of fasting and 5 days of recovery. Half of the female mice displayed great individual variation in TE, whereas male mice rarely exhibited daily torpor. In females, RBW at birth influenced TE, irrespective of body weight in adulthood; thus, female mice born with low RBWs displayed high TE in adulthood. In conclusion, we provide evidence that TE in mice differs among littermates, and that this variation is linked closely to heterogeneous nutritional experiences during the foetal period.