COLD THERMOGENESIS IN THE SUMMER-ACCLIMATIZED AND COLD-ACCLIMATED DOMESTIC-FOWL

1. Summer-acclimatized and cold-acclimated fowls, saline or propranolol treated, were exposed to air temperatures between 25 and 2°C. 2. V doto on integrated EMG activity regression was linear; its intercept was higher in the cold acclimated fowls. 3.Propranolol markedly reduced shivering and V doto; subsequently V doto recurred to normal with no change in EMG activity level in both groups. 4. These were interpreted to indicate the presence of obligatory non-shivering thermogenesis dependent on cold-acclimation and to suggest a possible capacity for regulatory non-shivering thermogenesis independent on cold-acclimation. © 1979.