Ultrastructure satudy of egyptian buffalo spermatozoa after thawing and capacitation

To investigate the ultrastructure of Egyptian buffalo spermatozoa after thawing and capacitation: three principal parts, the head, the neck and the tail have been evaluated by means of electron microscopy. The head is flat, oval or paddle, shaped with a square base, which provides a concave recess for the insertion of the tail. The acrosome tightly covers the anterior two thirds of the nucleus. The equatorial region distinguish the acrosome from the post-equatorial region that cover the caudal one third of the nucleus. The classical 9+9+2 fiber pattern which composes the axoneme was observed along three segments of the tail, namely middle, principal and terminal pieces. The axoneme is anteriorly bound by the mitochondrial helix (middle piece) and posteriorly by the fibrous helix (principal piece), except at the terminal piece. The border between the middle piece and principal piece was well defined due to the termination of the thick mitochondrial helix and the presence of the annualus. Some of the spermatozoa presented cytoplasmatic droplets, which appeared as stalk-like appendages. In conclusion, the results indicated that the capacitation of Egyptian buffalo spermatozoa followed by ultrastructure investigation enable us to improve the fertilization rate in order to obtain excellent embryos with high production rate. In addition, in vitro fertilization technlogy may be used in the field for improving the productivity of farm animals