Morphological and histochemical observations on oocyte atresia in Centrorhynchus corvi (Acanthocephala)

Abstract

A morphological and histochemical study has been made of atresia in oocytes in the ovarian balls of an acanthocephalan (Centrorhynchus corvi). Growing oocytes and mature oocytes have been observed to undergo atresia. With the start of atresia, the nuclear and cytoplasmic components are observed to be greatly altered. The atretic oocytes develop abnormal aggregations of cell components, which contain proteins, phospholipids and lipoproteins. It is suggested that the cellular products of degenerating oocytes are gradually absorbed by the supporting syncytium. The atresia of growing oocytes is greater in uninseminated than in inseminated females, which indicates that in the absence of a mating stimulus atresia occurs more frequently.