Ultrastructural analysis of degenerative changes of spermatogonia of Salmonidae from Ohrid lake during spermatogenesis

Vol 26 No 1 (2023): Acta Musei Macedonici Scientiarum Naturalium

Abstract

The purpose of these article is to represent the cytomorphological aspect of the spermatogonia in Ohrid trout (Salmo letnica (Karaman, 1924) and Ohrid belvica (Salmo ohridanus Steindachner, 1892) on ultrastructural level, which degenerate in the postspawning period. At certain sites in the wall of the seminiferous lobules of Ohrid trout and Ohrid belvica, in addition to normal spermatogonia, there are some that show clear signs of degeneration and are characterized by asymmetric shape, granular or vacuolated cytoplasm, condensed chromatin, and karyopicnotic features. On a level with certain lobules spermatogonia which separate from the walls of the lobules can be observed. We can notice presence of completely homogenous mass which originates from spermatogonia with delaminated cell membrane, as well as mitochondria with disintegrated crusts, vacuoles and poor cytoplasm or lysed parts of the cytoplasm. It has to be noted that spermatogonia whivh are situated next to the Sertoli cells are degenerated, as well as the Sertoli cells are. Our results which concern the cytomorphological characteristics of the spermatogonia which degenerate during the postspawning period correspond with findings of many other autors, as well as our previous results which concern the same or other teleost species. Our results show that in the period of rebuilding of the testicular parenchyma (postspawning period) the degenerative changes which are visible on a level with the spermatogonial population, should be explained as normal accompanying phenomenon which follows the initial phase of the future reproductive cycle whose intensive development happens in the later period, period of regeneration.