Thermal adjustments of steers ( Bos taurus ) to abrupt changes in environmental temperature

Body heat storage changes of cattle were measured by means of simultaneous direct and indirect calorimetry and by thermometry in an environment that alternated in temperature between 12 and 25 °C. When the calorimeter temperature was increased deep body temperature ( T c ) increased by approximately 0–5 °C, mean surface temperature ( T s ) by 3 °C and mean body temperature (determined from calorimetry, T b ) by 1 °C, but these increases were not fully sustained during the next 24 h. Changes in the three temperatures were related by the equation: δT b = αδT c +(1-α) δT s where a was found to be 0·89±0·027 (S.E.).