TREMATODES: Digenea spp. Flashcards
What is the predilection site for P. kellicotti, and what clinical signs can result from its infection?
- Lung parenchyma
- Developing cysts can lead to an intermitten cough, or in heave infections - severe cough, dyspnea, pneumothorax, bronchiectasis, hemoptysis, pneumonia, and death
Who are the abherrant hosts for Fascioloides magna?
Sheep and goats
A farmer had several cattle die due to F. magna. The cattle were pastured near or in the same pasture as adjacent white tailed deer. How would you test the white tailed deer to see if they also have F. magna?
Fecal sedimentation
As a result of increased burdens of F. hepatica in horses, will adults cause increased or decreased susceptibility to other diseases?
Adults to not form in horses, as well as people, as they are the accidental and abherrant hosts
What pathogenesis is associated with Platynosomum fastosum?
Hyperplastic bile ducts, leading to a palpable liver, icterus and death
Who are the FH’s or DH’s for lung fluke infections?
P. kellicotti infects dogs and cats
How many IH’s are commonly needed for completion of trematode life cycles?
2, the first being an aquatic snail
Who are the DH’s or FH’s?
White tailed deer, elk, caribou, wild cervids (spp. of the deer family)
What is the common name for Paramphistomum spp.?
Rumen fluke
Who are the DH’s or FH’s of rumen fluke infections?
Ruminants (buffalo, cattle, sheep, goats) and cervids (deer, antelope)
You find hundreds of this parasite during a necropsy of a sheep. It suffered from diarrhea, anemia, and anorexia. What is it?
Paraphistomum spp.
What predilection sites are associated with Paramphisotomum spp. infections?
Immatures = Duodenum
Adults = Rumen
Several sheep have fallen ill and died. You suspect Fascioloides magna is the cause of their deaths. What would you expect to find during necropsy?
A shredded/ diseased liver and immature flukes only
In the SE U.S.A., what seasons are you most likely to diagnose or find them on pastures? When is the optimal time for treatment?
- From fall to spring, as there is no transmission over the summer (due to heat, etc.)
- Most effective treatment is at the end of the year, Oct. to Dec., when there are only adults (or the largest amounts fo adults)
What diagnoses can be used for the liver fluke of cats?
- Double centrifugation with sugar
- Abdominal ultrasound
- Liver biopsy
True or False: Trematodes are geographically distributed based on the presence of their intermediate host.
True
How pathogenic are N. salmonicola to dogs and other canids?
Very, if they contain Neorickettsia helminthoeca
You find these operculated eggs in cattle. The cows are showing clinical signs of bottle jaw and anemia. During necrospy of those that died you expect to see what type of pathogenesis?
Pipestem liver due to Fasciola hepatica infections
Where do juvenile flukes, once inside the DH or FH, migrate to?
The bile duct, where they develop into adults and lay eggs
What is the common name for Platynosomum fastosum?
Liver fluke of Cats
Do adult Alaria spp. infections in DH’s or FH’s result in pathogenicity?
No, they have no associated clinical signs
Where does F. hepatica have a predilection site for? What pathogenesis are they associated with?
Bile ducts, where they migrate to and then feed. They cause irritation, fibrosis, anemia, bottle jaw, pipestem liver, diarrhea, and inappentence
What common disease name is associated with Platynosumum fastosum infections in cats?
Lizard poisoning
A farmer is worried about F. hepatica and F. magna, and wants to know how to decrease his animals’ exposure to the intermediate host. What do you tell him?
Don’t allow your animals to graze on wet/ marshy lands (source for aquatic snail IHs)
What will occur to cattle, horses, and pigs infected with F. magna?
Immature flukes will become adults and encyst, but they will not become patent
Where will immature stages and adults be found in hosts with Alaria infections?
Adults = Small intestine
Immatures = Lungs
Migrating metacercariae in PH’s can cause what phatogenesis?
Pulmonary hemorrhage
In the NE U.S.A., what seasons are you most likely to diagnose or find them on pastures? When is the optimal time for treatment?
- Found during the spring and fall, due to heavy winters (snow, etc.)
- Effective treatments are done toward the end of the winter season (March to June), when there are only adults
What diagnostics can be used to identify or confirm F. hepatica infections?
- Fecal sedimentation
- Bulk milk ELISA testing
- Necropsy
What species will experience clinical signs as a result of Fascioloides magna infections?
- AH’s like Sheep and goats
- DH or FH, and DEH’s will not experience clinical signs
What structural feature can be used for identification of Alaria trematodes, as well as for these parasites to wrap around intestinal mucosa?
Ventral groove
Who are the DH’s or FH’s for Fasciola hepatica?
Ruminants
What stage is causing clinical signs with Paramphistomum spp. in hosts, and where are they located?
Juveniles, found in the duodenum
Who are the DH’s or FH’s for intetinal fluke infections?
Dogs, cats, foxes, and minks
What diagnostic can be used for the identication of trematodes, based on their egg size and weight?
Fecal sedimentation
What is the 2nd IH for N. salmonicola?
Salmonid fish (salmon, trout, graylings, etc.)
What clinical signs are associated with N. salmincola infections?
Enteritis
Who are the more common paratenic hosts of Platynosumum fastosum?
Lizards (geckos, skins, anoles) and toads
Who are the AH or accidental hosts for F. hepatica?
Horses and people
Which drug - Oxyclozanide or Niclosamide - can be used for the elimination of both mature and immature stages of Paraphistomum?
Oxy = Both
Niclo = Only immature
What is the PPP for Fascioloides magna, or deer fluke?
8 months
What is the 2nd IH for Alaria spp. infections?
Tadpoles
What can be used for treatment of F. hepatica?
Flukicides, NOT PRAZIQUNATEL
Who are the DH’ sor FH’s for N. salmincola?
Dogs, cats, people, minks, raccoons, or any fish-eating mammals
What is the PPP of Nanophyetus salmincola?
About 1 week
Who are the DEH’s of Fascioloides magna?
Cattle, horses, and pigs
What is the PPP of Platynosomum fastosum?
3 monts
What is the predilection site for adult salmon poisoning flukes?
Small intestine
What are some common charateristics shared by trematodes?
- Doro-ventrally flattened
- Oral and ventral suckers (ventral located diff.)
- Incomplete alimentary canal (no anus)
- Hermaphroditic
- Indirect life cycle
- Aquatic snail common IH
In the DH, what will occur with F. magna infections?
Juvenile flukes wander through the liver parenchyma, forming cysts around the adults, which lay their eggs that are released from the cysts and into the feces
What is the common name for Alaria spp.?
Intestinal fluke
What secondary infection is associated with Paraphistomum, which can cause death?
Clostridium spp.
What is the common name for Fascioloides magna?
Deer fluke, Large american liver fluke
What is the difference between a miracidia, cercariae, and metacercariae?
Miracidium = free-living larva, ciliated
Circacidium = tadpole-like larvae, final and free swimming
Metarcaeracium = encysted resting stage of trematode larvae, ingested by DH’s
Ruminants with F. hepatica infections have an increased or decreased resistance to other diseases?
Decreased
Who are the DH’s or FH’s for Platynosomum fastosum?
Felids
When does a miracidium develop into a sporocyst?
In the IH, where it develops from a miracidiae into a sporocyst, and then into a cercariae that leaves the IH
How can Paraphistomum infections be diagnosed?
Clinical signs (young, gazing habits) and the presence of acute disease
What is the PPP for P. kellicotti?
4 - 5 weeks
What will occur to sheep and goats with F. magna infections?
Immature flukes migrate through the liver, never becoming adults, leading to death via liver failure
During necropsy you find this diseased liver with pipestem shown. What is the associated parasite, and how would you diagnose it in living animals?
Fasciola hepatica and fecal sedimentation
A dog who’s owner loves fishing in Canada presents for fever, enteritis, and diarrhea. What is at the top of your differential list?
Nanophyetus salmincola
What is the 2nd IH for the liver fluke of cats?
Crustaceans
What is the PPP for Alaria spp.?
5 weeks
What is carried by N. salmincola?
Neorichettsia helminthoeca, which causes the salmon poisoning (severe hemorrhapgic enteritis)
What is the common name for Nanophyetus salmincola?
Salmon poisoning fluke
What is the common name for Paragonimus kellicotti?
Lung fluke
What physical feature is associated with Paraphistomum adult flukes?
Their ventral sucker is at their posterior end
What clinical signs are associated with N. salmonicola carrying Neorickettsia helminthoeca?
Sudden fever, hemorraghic enteritis, enlarged ln’s, vomiting, diarrhea, weight loss, HIGH MORTALITY
What is the PPP for Fasciola hepatica?
10 - 12 weeks
A 5 year old cat from Florida comes into your clinic with a palpable liver, and upon examination, you find signs of icterus on the inner pinna. What would you expect to find?
Platysonosum fastotum, a small egg up to 50 µm
What is the common name for Fasciola hepatica?
Liver fluke
What is the 2nd IH for Paragonimus kellicotti?
Crayfish
What is the PPP of Paraphistomum spp.?
7 - 10 weeks
While relatively non-pathogenic, what can result from heavy burdens?
Severe enteritis, dehydration, bottle jaw, anemia, hemorrhage
A farmer calls you during the winter time, when there is snow on the ground, about his sheep that are suffering from anemia and bottle jaw. He is worried that his sheep are suffering from Haemonchus contortus. What is at the top of your differential list?
Fasciola hepatica
Are any PH’s associated with Alaria spp. infections?
Yes
Frogs, snakes, mice, birds, wild boar, and people
What diagnostics can be used for lung fluke infections?
- Radiographs
- Fecal sedimentation
- Transtracheal wash
