Induced Cycles of Egg Production in the Chukar Partridge

Abstract

REPRODUCTION in most wild passerine and gallinaceous birds is much the same in that most are seasonal layers and produce their young in the spring of the year, when favorable light and temperature conditions prevail. Under domestication, chukars (Alectoris graeca chukar) and pheasants (Phasianus colchicus) can be induced to lay in midwinter, rather than in the spring, provided the birds are preconditioned by short day lengths before being exposed to long daily photoperiods (Funk et al., 1942). Rowan (1929) demonstrated that repeated cycles of gonadal development could be induced in slate-colored juncos (Junco hyemalis) by subjecting these birds to alternating periods of short and long days. His results were substantiated by Wolfson (1954), who reported that multiple cycles of gonadal development, fat deposition, and periods of molt could be induced in juncos and white-crowned sparrows (Zonotrichia leucophrys leucophrys) by subjecting these species to alternating periods of short (9L:15D) and long…