Morphosis and ultrastructure of the spermatozoon of Salvelinus leucomaenis
The morphous and ultrastructural organization of Salvelinus leucomaenis spermatozoon was observed by scanning and transmission electron microscopes.The spermatozoon with no acrosome consisted of the head,middle piece and the tail.The head of the spermatozoon was oval shape and mainly consisted of the nucleus.The nucleus,within which there were some netlike gaps,consisted of electron dense chromatin materials.In posterior extremity of the nucleus,implantation fossa trapped into the internal to the 1/3.The middle piece consisted of centriolar complex and sleeve.The proximal centriole,which is made up of nine triplets of peripheral microtubules,is perpendicular to the distal centriol which extended downward to form the kinetosome of axial filament.The sleeve,which contained a high number of mitochondria and two kinds of vesicles,was connected to the posterior end of the nucleus.Some mitochondria were fused with each other and formed a complex chondriosome.The tail of Salvelinus leucomaenis spermatozoon was slim and long.The main composition of the tail was axoneme whose structure was the typical model of "9+2" and surrounded by vesicles.The plasma membrane was prominent symmetrically up and down to form two lateral fins with different sizes.