Figure 6.

Body temperatures of a single female MF1 mouse measured at 1-minute intervals using an implanted body temperature transmitter (e-mitter Minimitter Inc) for 7 days prior to breeding and for 7 days at peak lactation. Data are screened to include only times when the animals are at rest, and then averaged over 30-minute periods within each day. The error bars refer to the s.d. for day-to-day variability (n=7 for each data set). During lactation, the body temperature is consistently elevated approximately 1.5°C higher than that prior to breeding during the light phase and much of the dark phase. Dark bar indicates period when lights out (J. R. Speakman, K. Drerrer, F. J. Munro & C. T. Troup 2005, unpublished data).