Echinococcus multilocularis Leuckart, 1863 (Taeniidae): new data on sperm ultrastructure

Area of Science:

• Parasitology
• Cell Biology
• Helminthology

Background:

• Understanding cestode spermatozoon ultrastructure is crucial for parasitic disease research.
• Echinococcus species cause significant human and animal health issues.

Purpose of the Study:

• To describe the ultrastructural organization of the mature Echinococcus multilocularis spermatozoon.
• To compare E. multilocularis sperm ultrastructure with other cestodes, particularly Taenia species.

Main Methods:

• Transmission electron microscopy (TEM) was used to examine E. multilocularis sperm.
• Ultrastructural characteristics were documented and compared with existing literature.

Main Results:

• E. multilocularis spermatozoon is filiform, lacks mitochondria, and possesses a single axoneme.
• Key features include crested bodies, spiralled cortical microtubules, nucleus, periaxonemal sheath, and intracytoplasmic walls.
• A significant finding is the presence of two helical crested bodies, unlike the single one found in Taenia species.

Conclusions:

• The ultrastructure of E. multilocularis spermatozoon aligns with Type VII tapeworm sperm.
• The presence of two crested bodies may be a distinguishing feature of the Echinococcus genus.
• Further studies on Echinococcus species are needed to confirm this characteristic.