Structure of the yolk syncytial layer in Teleostei and analogous structures in animals of the meroblastic type of development

Resumo

The structure of the yolk syncytial layer (YSL) of the larvae of two cyprinids, Danio rerio and Cyprinus carpio koi, has been studied by transmission electron microscopy and by the histological methods. The structure of the YSL of these taxonomically related species of Teleostei is characterized by both similarity and dissimilarity in particular features, related to the overall shape of YSL, functional regionalization, and programmed death. Original and published data on the morphofunctional structure of the YSL have been discussed for representatives of Teleostei, Myxini, Chondrichthyes, Lepisosteiformes and Cephalopoda.