A CYTOLOGICAL AND CYTOCHEMICAL STUDY OF THE SHELL GLAND OF THE DOMESTIC HEN

Abstract

A cytological and cytochemical study has been made of the oviducts of hens producing thick shelled eggs and of hens producing thin shelled eggs, with special reference to the shell gland. No significant differences between them were discovered. The inner surface of the oviduct of the hen is lined with ciliated epithelium containing two types of cells, ciliated and goblet. Lying under the ciliated lining are the tubular glands of the oviduct. The Golgi apparatus has been described in the several types of cells. The secretory products of these cells have been identified in the various parts of the oviduct. Small amounts of calcium were shown to be present in the oviduct by one of several techniques, the others giving negative results. Slight positive results were obtained for the presence of phosphates. Alkaline phosphatase was present in slight and varying amounts uniformly distributed in the oviduct, but acid phosphatase was confined to the ciliated epithelium. Glycogen was not present in the glandular tissues. The deposition of calcium as egg shell seems to be different from that in bone formation. Possible mechanisms of egg shell formation are discussed.