EFFECTS OF LIGHT AND TEMPERATURE ON ANTICIPATORY FEEDING BY BROILERS

The objective of this research was to determine the effects of daily c ycles of light intensity and temperature on anticipatory feeding by br oilers. Broilers were maintained on litter in environmental chambers w ith feed provided for 12 h/d. Feed consumption was recorded by compute r every 30 min and summarized for 2- and 24-h periods. In Trial 1, lig hting was at 16 lx for 12 h and at 94 lx for 12 h each day. Feed was p rovided either during the 16- or 94-lx period. Broilers consumed more feed at the onset of feeding and at the end of the feeding period than at other times in both treatments. In Trials 2 and 3, the chamber tem perature was cycled such that a 12-h feeding period was provided at ei ther 32 or 16 C. Broilers consumed more feed at the onset of feeding t han at other times but did not increase consumption at the end of the feeding period. The results indicate anticipatory feeding is enabled b y cyclic lighting intensity but not by cyclic temperature. In Trial 4, the light intensity and temperature were cyclic. Feed was provided du ring high light intensity and at maximum temperatures. Feed consumptio n increased when temperature was declining, indicating broilers respon ded to the reduced temperature. The results show that a period of dark ness is not required for anticipatory feeding and that environmental t emperatures and lighting typical of curtain-sided broiler houses alter feed consumption patterns.