Cestodes Flashcards
Pseudophyllidea cestodes (2)
- Spirometra
- Diphyllobothrium
Cyclophyllidea cestodes (4)
- Taenia
- Echinococcus
- Dipylidium
- Hymenolepis
acetabula
suckers
rostellum
hooks
scolex
basically the head, is the vibe
neck
part of worm with immature proglottids
cestode
tapeworm
proglottid
individual segment of tapeworm which contains male and female reproductive organs
Differences between Pseudo- and Cyclo- phyllidea (5)
strobilia
main body of worm, linear series of proglottids
cyclophyllidean lifecycle
round egg develops into oncosphere which then becomes one of four different kinds of cysts before becoming an adult cestode
4 Types of Cyclophyllidean Cysts
- Cysticercus
- Cysticercoid
- Coenurus
- Hydatid
Pseudophyllidean Life Cycle
ovoid egg to round coracidium to procercoid to plerocercoid to adult cestode
Intermediate hosts of Cyclophyllidean?
terrestrial
Intermediate hosts of Pseudophyllidean?
aquatic (copepods –> fish)
Zipper worm (Spirometra mansonoides)
pseudophyllidean stomach intestinal worm of cats, they get it from eating fish; worldwide distribution
Diphyllobothrium
pseudophyllidean worm which typically infects humans, dogs, or bears, common in the PNW, Great Lakes, and Canada
How many genital pores per segment of Taenia?
1
Taenia sagninata (beef tapeworm)
IH = cattle
DH = humans
Taenia solium (pork tapeworm)
IH = swine or humans
DH = humans
Taenia pisiformis (rabbit tapeworm)
IH = rabbits
DH = dogs
Taenia hydaginata
IH = sheep, cattle
DH = dog, human
Taenia lifecycle
herbivore ingests eggs from feces, cysticerci develop in tissue, carnivore eats this infectious tissue, develops into adult in small intestine
Neurocysticercosis
neurological signs in humans due to Taenia solium
Taenia solium detection and prevention
larvae in muscle at slaughterhouse will have nodules
can also see the cysticerci on underside of pig tongue
Where are taenia solium common?
free range pigs (and Central and South America)
Measly meat
due to tapeworms (solium and saginata)
Taenia solium clinical signs in humans
NEUROLOGICAL
Taenia saginata clinical signs in humans
diarrhea and weight loss
Taenia pisiformis rabbit diagnosis
larval cysts (cysticercus) in liver and peritoneal cavity on the viscera; also they’ll have diarrhea and an itchy butt
Uniqueness of Taenia multiceps
causes larval cysts in the brain, cranium, and spinal cord of intermediate hosts (sheep and goats) which don’t stop growing!
ataxia, circling, blindess
this is the one that looks like that weird sand you had as a kid
Smallest taenid?
Echinococcus granulosus
Definitive host of Echinococcus
dogs, coyotes, wolves, and other canids
Clinical Signs of Echinococcus granulosus
none in definitive host, but intermediate hosts will get large cysts which may rupture in vital organs and can cause sudden death; mainly a problem in sheep
Echinococcus multiocularis
DH = dog/canid, IH = humans, causes liver disease and death and easily confused with cancer
Intermediate host of Dipylidium caninum?
fleas and lice
What parasite is responsible for butt scootin’ in dogs?
Dipylidium caninum (pruritis ani is the vet term for butt scootin’)
Anoplocephala eggs
unusually shaped, can be square, traingular, etc
What type of tapeworm is the exception to praziquantel treatment?
Anaplocephalidae - better with benzimadazoles
Anoplocephala perfoliata
D-shaped eggs, adult worms are gross (duh), collect at ileocecal valve in horses and cause colic
(bonus: intermediate host is mites!)
