Helminthology Flashcards
5 Groups included under helmithology
1) Trematoda
2) Cestoda
3) Nematoda
4) Nematomorphs
5) Acanthocephala
Digenetic
2 beginnings (Normally has two intermediate hosts)
Morphology of Digenetic Flukes
D/V flattened Smooth or spiny tegument Oral sucker for feeding Ventral sucker for attachment Digestive, excretory, and nervous systems Complex repro system - hermaphroditic
Sexual Classification of Flukes
Hermaphroditic
Typical Digenetic Fluke Life Cycle
Operculated egg–>Miracidium–>Sporocyst–>Redia–> Cercaria–>Metacercaria–>Adult fluke
Operculated Egg
Produced by hermaphroditic fluke
Operculum (door) at one end (pole)
Undifferentiated mass of cells
Miracidium
Triangular w/ broad ant. end; covered with cilia or hairs
First Intermediate Host for Digenetic Fluke
Snail
Sporocyst
Develops in snail; Rediae develop inside of it
Redia
develop w/in sporocyst; inside develops many cercariae
Cercaria
Leaves via snail’s skin to aquatic environment
3 Things Cercaria can do
1) Penetrate or be ingested by 2nd int. host
2) attach to vegetation and become encysted
3) Penetrate definitive host directly
8 Things to know for each parasite
1) Host
2) Habitat
3) Identification (visual)
4) Life Cycle
5) Clinical signs
6) Dx
7) Tx & control
8) Zoonotic potential
Platyhelminthes are called _____ and are divided into 3 classes.
Flatworms
- Trematoda (flukes)
- Eucestoda (true tapeworms)
- Cotyloda (pseudotapeworms)
Monogenetic trematodes are _____, usually associated with aquatic environments. Therefore, they infest the skin and or the gills of? They DO NOT occur in domestic animals
Ectoparasites; fish, amphibians and reptiles,
Digenetic trematodes are _____ of both domestic and wild animals and HUMANS
Endoparasites
If the cercariae stage of the developing fluke penatrates or is ingested by the 2nd int. host or encysts upon vegetation, it enters into the _____ or the infective stage.
Metacercaria
Metacercaria must reach the _____ host to complete the life cycle.
Definitive
