Helminth Introduction Flashcards
What kind of parasites are helminths?
Endoparasites (like protozoa)
What is the body shape of Acanthocephalans?
Long
What is the body shape of nematodes?
Long
What is the body shape of cestodes?
Segmented
What is the body shape of trematodes?
Leaf-like
What is coleomate?
There is a body cavity with mesoderm keeping everything in the right position
What is pseudoceolomate?
Has a body cavity but the mesoderm only covers the inner lining so the internal organs are loosely in place
What is acoelomate?
There is no body cavity, it is all parenchyma/tissue
What are the acoelomates?
Trematodes
Cestodes
What are the pseudocoelomates?
Nematodes
Acanthocephalans
What kind of digestive tract do nematodes have?
Complete, they have a feeding mechanism and excretory mechanism
What kind of digestive tract do trematodes have?
Partial digestive tract
They have a feeding mechanism but no excretory
What kind of digestive tract do cestodes have?
They do not have a digestive tract
What kind of digestive tract do acanthocephalans have?
They do not have a digestive tract
Which helminths are dioecious?
Acanthoccephalans and
Nematodes
Which helminths are monoecious?
Cestodes and Trematodes
What are the general characteristics of nematodes?
Long, round, unsegmented
Pseudocoelomate
Complete digestive tract
Dioecious
What are the general characteristics of cestodes?
Long, dorsoventrally flat, segmented
Acoelomate
Lack digestive tract
Monoecious
What are the general characteristics of trematodes?
Dorsoventrally flattened, unsegmented
Acoelomate
Incomplete digestive tract
Monoecious (except for Schistosoma, which the make and female are separate but very close together)
Why are the female and male Schistosoma very close together?
The female is very small and the male gives her a place to blood-feed and a way to get to where she needs to be safely
What are the general characteristics of acanthocephalans?
Long, rounded, unsegmented Pseudocoelomate Lack digestive tract Dioecious Anterior spiny proboscis
Is the female or male acanthocephalan larger?
Female
What does the Acanthocephalan life cycle require?
An intermediate host
What causes inflammation/pathology with Acanthocephalans?
Proboscis
What is the definitive host of Macracanthorhynchus hirudinaceus?
Swine (adult worms in small intestine)
What is the intermediate host of Macracanthorhynchus hirudinaceus?
Grubs (larvae)
What is the zoonosis of Marcacanthorhynchus hirudinaceus?
May be zoonotic
What is the PPP of Marcanthorhynchus hirudinaceus?
2-3 months
What is the pathogenesis and clinical signs of Marcanthorhynchus hirudinaceus?
Usually no clinical signs
Possible gastrointestinal signs (enteritis/pain, decrease in feeding or weight gain, diarrhea)
What is the diagnosis of Marcanthorhynchus hirudinaceus?
Eggs in pig feces
What is the definitive host of Macracanthorhynchus ingens?
Mainly raccoons, but occasional dogs
What is the intermediate host of Macracanthorhynchus ingens?
Millipedes
