Ultrastractural studies on the parasitic worm Trichinella Spiralis

This paper reports on the ultrastructure of Trichinella spiralis using transmission and scanning electron microscope. Male and Female adult worms were recovered from L1 and L2 infective larvae, which were isolated from striated mouse muscle. The adult male, which is smaller than adult female, undergoes the most drastic morphological changes and develops the copulatory appendages posteriorly. The female adult worm is larger and broader than the male; posterior, only an anus is visible. In longitudinal section the seminal vesicle of the male has a thick wall with elongated cells. Sperms within the seminal vesicle are amoeboid. Mature sperms within the vas deference have pale granular cytoplasm with a large, dense nucleus ringed with mitochondria. Primary oocytes, which mature in the ventral ovarian cavity, can be seen to developing a microvillous border. Larger mature oocytes have a well-developed microvillus border. Spermatheca is a thick-walled fertilizing chamber which in the fertilized female contains numerous sperm. Stichocyte are the most prominent cells of the anterior part of the worm.