ULTRASTRUCTURAL OBSERVATION ON THE MEIOTIC DIVISION OF PRIMARY SPERMATOCYTES OF PARAGON IMUS SKRJABINI

The present paper is the first report on the ulfrastructure of the meiotic division of primary spermatocytes of Paragonimus skrjabini using transmission electron microscopy. Fresh testes specimens were isolated from the adult worm of P. skrjabini under the dissection microscope before being fixed with 2.5% glutaraldehyde. The prophase of the first meiotic division of primary spermatocytes consisted of leptotene, zygotene, pachytene and diakinesis stages. Observation were made on the prophase, metaphase 1, anaphase 1 and interkinesis. The meiotic division in the germ cells of the male worm was similar to that in mammals and it was of a terminal type. During the division of germ cells of male P. skrjabini, the primary Spermatocytes formed large clusters. Our observation showed that cytokinesis was incomplete. Germ cells with synchronous development were linked by intercellular bridges. These bridges persisted until the last moment when individual spermatozoa were released from the clusters.