Ultrastructure of spermatozoa of marine teleosts Umbrina cirrosa L. and Diplodus puntazzo (Cetti) and preliminary observations on effects of cryopreservation.

Abstract

Scanning and transmission electron microscopy investigated the sperm types of U. cirrosa and D. puntazzo. The spermatozoa of these two marine teleosts are simply organised and lack an acrosome. The mature sperm of U. cirrosa has an ovoid head and a long tail inserted laterally, and in the midpiece of the tail five spherical mitochondria are arranged around the axoneme. The sperm head of D. puntazzo is spherical, the tail is nearly perpendicular to the head and the flagellum is inserted in a deep nuclear fossa. The midpiece of the tail contains only one mitochondrion. Preliminary observations on cryopreserved sperm of D. puntazzo revealed unmodified chromatin condensation, but cytoplasmic vesicles were common in swelling spermatozoa. These data could be useful in fisheries management