VPA 211: General Veterinary Parasitology and Helminthology (3+1)

MORPHOLOGY OF TRICHINELLA SPIRALIS

Genus	Trichinella
Species	T.spiralis
Host	Pig, rat, man and also seen in dog, cat
Location	Adult worms are seen in the small intestine while larvae are seen in striated muscles like diaphragm ,tongue, intercostal and mandibular muscle
Common name	Garbage worm and Trichina worm

• The worm causes - Trichinellosis or "Raw pork disease in man".

Morphology

• Male worm is about 1.5mm. Female is about 3 - 4mm. In both the sexes anterior end is blunt and Oesophagus is very long (about 1/3 of total body length).
• In male, spicule is absent, in female vulva is situated near the middle of oesophageal region.
• Male tail end has a pair of lateral flap on either side of cloacal opening and 2 pairs of papillae occur just behind the lateral flap.
• Female is ovo-viviparous. But egg hatch in the uterus itself .

Female	Male