Tapeworms Flashcards
What are the general characteristics of tapeworms?
Flattened in shape
Lack a body cavity
Hermaphroditic
Digestive tract incomplete
How do you classify tapeworms?
Phylum: Platyhelminthes
Class: Cestoidea (Cestoda)
Why are the orders of tapeworms?
Cyclophyllidea: true tapeworm
Pseudophyllidea (diphyllobothriidea): false tapeworm
What are some genera of Cystos?
Taenia, echinoccocus, dipylidium
What are some genera of Pseudos?
Diphyllobothrium and spirometra
What are the true tapeworms of dogs and cats?
Dipylidium caninum
Taenia pisiformis
Taenia taeniaeformis
Taenia multiceps
Whar are some other species of true tapeworms?
Echinococcus granulosus
Echinococcus multilocularis
What are some species of false tapeworms?
Diphyllobothriidea
Spirometra mansonoides
Diphyllobothrium latum
What is the definitive host if Dipylidium caninum?
Dog and cat
In the small intestine
Why are the intermediate hosts of Dipylidium caninum?
Flea (body cavity)
Ctenocephalides felis (dogs and cats, most common)
Ctenocephalides Canis (less common)
Lice (rare)
Larval infective stage of Dipylidium caninum
Cysticercoid
Dipylidium caninum lifecycle
Indirect
Prepatent: 2-3 weeks
Double-pored
Dipylidium caninum steps in lifecycle
- Infected dog or cat pass feces with proglottids (with Dipy eggs), they rupture and release eggs into environment
- Flea larvae ingest the eggs in the environment and eggs develop into cysticercoids
- Cysticercoids in body cavity of adult fleas
- Dogs and cats infected by ingesting fleas
- Cysticercoids develop into adult tapeworms in small intestine
Clinical signs of Dipylidium caninum
Perianal irritation
White rice grain-like proglottids in feces
Rough hair coat
Lethargy
How do you diagnose Dipylidium caninum?
Direct smear (more effective)
Fecal flotation
How do you treat Dipylidium caninum?
Praziquantel
Combination of flea control and heart worm preventative
Public health concerns of Dipylidium caninum
Zoonotic
Observed in children following ingestion of flea containing cysticercoid
Found in intestines
Causes mild disease
Treatable
What species of Taenia are common in dogs and cats?
Taenia pisiformis (dog)
Taenia taeniaeformis (cat)
Taenia multiceps (dog)
How is the scolex of Taenia in North America?
Armed with 2 rows of hooks
Eggs of the Taenia species
Thick shell surrounds the ochosphere which contain hooklets (in center)
What are the host of Taenia pisiformis?
Definitive: Dogs (small intestine)
Intermediate: rabbits (abdominal cavity)
What is the larval infective stage of Taenia pisiformis?
Cysticercus
Lifecycle of Taenia pisiformis
Indirect
Requires a rabbit as the intermediate host
Prepatent: 6-8 weeks
Taenia pisiformis lifecycle steps
- Infected dogs pass feces with proglottids with the eggs, eggs rupture then into environment
- Intermediate host ingest egg and develop into cysticercus
- Infected dogs eats infected rabbit
- Cysticercus develop into adult tapeworms
What are the clinical signs of Taenia pisiformis and taeniaeformis?
Symptoms depend on worm burden, age and body condition
Enteritis
Diarrhea
Lethargy
How do you diagnose Taenia species (all)?
Direct smear
Fecal flotation
How do you treat Taenia species (all)?
Praziquantel and Fendendazole
Public health significance of Taenia species (all)
Zoonotic (low risk of human becoming infected)
Host of Taenia taeniaeformis
Definitive: cats (small intestine)
Intermediate: rodents (abdominal cavity)
Type of larval infective stage of Taenia taeniaeformis ?
Strobilocercus
Lifecycle of Taenia taeniaeformis?
Indirect and requires a rodent as an intermediate host
Prepatent: 6-8 weeks
Taenia taeniaeformis lifecycle steps
- Infected cats pass feces with proglottids with the eggs, proglottids rupture then into environment
- Intermediate host ingest egg and develop into strobilocercus
- Infected cat eats infected rodent
- Strobilocercus develop into adult tapeworms
Hosts of Taenia multiceps
Definitive: dogs (small intestine)
Intermediate: sheep, goats and man (brain and SC)
Type of larval infective stage of Taenia multiceps
Coenurus
Lifecycle of Taenia multiceps
Indirect
Prepatent: 6-8 weeks
Produces a neurological condition called GID in sheep
Taenia multiceps lifecycle steps
- Infected dogs pass feces with proglottids with the eggs, proglottids rupture then into environment
- Intermediate host ingest egg and develop into cornurus
- Infected dog eats infected sheep or goat
- Coenurus develop into adult tapeworms
What are the clinical signs of the infected hosts of Taeniaeformis multiceps?
Blindness
Uncoordination
Walking in circles
Head pressing
Death may occur
