Practical parasitology
Dipylidium caninum
* Common name: double-pored tape worm.
* Life cycle: indirect
* Final host: canine
* Intermediate host: fleas & lice
* Larval stage (mesocestode): cysticercoid
* Diagnosis:
A- Ante mortem:
1- Gravid proglottid: which resemble cucumber seed with lateral pores on each side. may be found in feces;
2- Egg, occur in packets; may be find packets or individual eggs on fecal flotation.
B- Postmortem:
1- Up to 50cm in length; scolex with four suckers, retractable rostellum armed with three rows of rosethorn-shaped hooks; mature and gravid segments longer than wide, cucumber seed shaped, doubled-pored; lives in small intestine.
Hymenolepis nana (Dwarf tapeworm) & Hymenolepis diminuta (Rat tapeworm)
* Final host: Humans & rodents
* Intermediate Host: Larval and adult beetles
* Mesoestode: cysticercoid
* Location: small intestine
* Diagnosis:
1- Hymenolepis nana:
- Small tapeworm 4cm in length.
- Scolex has rostellum with hooks
- Proglottids are wider than long with lateral genital pore,
the testes are 3 lobes and the ovary is circular in shape
appear as four lobe in proglottid.
2- Hymenolepis dimunata:
- Slight larger than H. nana but still very small 6cm in length.
- Scolex has very small rostellum with no hooks
- Proglottid same as H. nana but larger
3- Hymenolepis eggs:
- Eggs are oval to spherical and almost colorless
and contain on embryo with 3 pairs from hooks.
- H. nana eggs has polar filaments.
- H. dimunata do not polar filaments.
Diphyllobothrium latum
* Common name: broad fish tapeworm.
* Life cycle: indirect
* Final host: dogs, cats, human, pigs, and bear.
* First Intermediate host: copepod
* Second Intermediate host: fresh water fishes
* Mesocestode: plerocercoid
* Diagnosis:
A- Ante mortem:
1- In definitive host: eggs are released through the uterine pore.
2- Eggs are may be found on fecal flotation.
3- Eggs are ovoid, operculated, yellowish, rounded at both ends.
B- Postmortem:
1- Definitive host: 1.5-4meter in length, scolex with two bothria, segments wider than long, gravid segments with central uterine pore and rosette-shaped uterus; found in the small intestine.
Spirometra mansoni
* Life cycle: indirect
* Final host: dogs & cats
* First Intermediate host: copepod
* Second Intermediate host: water snakes and frogs.
* Mesocestode: plerocercoid called ( sparganum).
* Diagnosis:
A- Ante mortem:
1- In the definitive host: eggs are released through the uterine pore.
2- Eggs may be found in fecal flotation.
3- Eggs are ovoid, operculated pointed at both ends; may be confused with flukes eggs.
B- Postmortem:
1- Definitive host: slightly pinkish tape worm up to 75cm in length, scolex with two bothria, gravid segments with central uterine pore and spiraled uterus, found in the small intestine.
2- Second intermediate host: sparganosis is provisionally identification upon finding the ribbon like, whitish spargana (plerocercoids) within the musculature.