The Effect of Light on Performance and Behavior in Diethylstilbestrol-Treated Male Turkey Broilers

Abstract It has been a common observation of commercial turkey growers that meat flocks vary in body weight, feathering and fat finish depending on the time of year in which they are grown. This has usually been explained on the basis of the effects of environmental temperature on feed consumption. Such a relationship does exist (author's unpublished data). However, light stimulation may also be involved either indirectly through an effect on sexual development (Margolf et al., 1947) or through some more direct neurophysiological path. There is little literature on the effects of light on growing turkeys. McCartney (1956) has concluded that turkeys require at least 13, and possibly 15, hours of light per day for maximum growth and feed efficiency. In addition he observed the degree of stagginess in males at 24 and 28 weeks of age to be associated with longer daily periods of light. Rate of feather development has …