State of Determination of the Antlerogenic Tissues with Special Reference to Double-head Formation

Abstract

The developmental conditions for the growth of primary cranial appendages and secondary or subsequent antlers are discussed with special regard to ortho- and heterotopic double-head formation. We hypothesize that the cells of the pedicle periosteum, being derivatives of the initial or antlerogenic periosteum which is determined for the formation of primary cranial appendages, are equally endowed with special antlerogenic tendencies. The hormonally controlled activation of these tendencies is possible even if previous casting of the old antlers has not taken place, and no casting wound arises at the top of the pedicle. The fact that antler regeneration occurs regardless of previous detachment of the old antlers indicates that the stimulus for regeneration is not antler casting but the death of the velvet antler. Antler regeneration, like sequestration of the old antler, is thus hormonally suppressed for some months after velvet shedding.