Dynamic and static responses of total heat production of broiler chickens to step changes in temperature and light intensity

The objective of the reported research in this article is to model the stat ic and dynamic response of the heat production of broiler chickens (1 to 35 days old) to step changes in temperature and light intensity. The static r esponse was quantified by means of the steady state gain. The dynamic respo nse was quantified by means of a time constant. Based on 243 data sets, it was concluded that the steady state gain for the response of heat productio n was -0.25 Wkg(-1)degrees C-1 and -0.32 Wkg(-1 degrees) C-1 on average for a step up (n = 30) and a step down (n = 30) in air temperature, respective ly. The steady state gain of the response of heat production was 4.7 Wkg(-1 ) and 4.1 Wkg(-1) on average for a step up (n = 91) and a step down (n = 92 ) in light intensity, respectively The average time constant of heat produc tion to a step up (n = 30) in temperature was 13.6 min and 9.2 min far a st ep down (n = 30). The average time constant to a step up in = 91) of Eight intensity was 8.9 min and 18.2 min for a step down (n = 92). Knowledge of s tatic and dynamic hear production responses is important for optimizing tem perature control and light schemes in broiler houses.