15 Cestodes Flashcards
What is the common name of cestodes?
Tapeworms!
What are the defining features of cestodes?
Segmented body, scolex with hooks/suckers/both, no body cavity, no GI tract, hermaphroditic w/ reproductive organs in each proglottid
Where do cestode larvae live?
Various tissue types in intermediate hosts
T or F: after becoming a strobilocercus, a cestode larvae then develops into a cysticercus.
F
What type of cestode larvae can be in a coenurus form, and what is it?
Cysticercoid – a cyst with multiple invaginations each containing a scolex, which can break off in the host
What type of cestode larvae can be in a hydatid form, and what is it?
Cysticercoid – a cyst containing multiple ‘brood capsules’, each of which contains a scolex
What type of cestode larvae does not have a bladder?
Tetrathyridium
Describe the lifecycle of Dipylidium caninum.
Flea larvae eats parasite eggs –> flea matures and moves onto host –> host eats flea during grooming –> parasite larvae migrate to small intestine –> worms mature in small intestine –> proglottids containing eggs are shed in feces
T or F: Taenia spp in dogs and cats are zoonotic.
F
What are the tapeworms of humans?
Taenia solium and Taenia saginata
What are the intermediate hosts of T. solium and T. saginata?
Pigs and cows
What is the difference of a human ingesting T. solium or T. saginata eggs versus larvae?
If a human ingests the egg, they will probably get severe disease and may die. If they ingest the larvae, they will end up with adult worms and be just fine
What species are affected by Mesocestoides?
Carnivores
What happens if a dog or cat is infected with the egg vs the larvae of Mesocestoides?
Egg –> will lead to asexually reproducing larvae that can cause peritoneal larval cestodiasis
Larvae –> will lead to an adult worm infection (non-pathogenic)
What are the definitive hosts for Echinococcus spp.?
Dogs, less commonly cats
