Trematode Parasites of Veterinary Importance Flashcards
Lecture 31 & 32
general morphology
dorsoventrally flattened
bilaterally symmetrical
Male & female reproductive organs
Lifecycle involves 2 IH
-mostly aquatic
-1st IH always snail
Parasitic in all systems of vertebrae DH
flukes have
flat leaf like body with both male and female reproductive systems
Paragonimus kellicoti
Lung fluke
DH: dogs, cats, people
acquired by ingestion of uncooked crayfish
Cause of respiratory disease
Dx by fecal
Paragonimus kellicoti respiratory disease symtoms
hard time breathing
dyspnea
pneumothorax in extreme cases
Zoonotic paragonimiasis
Foodborne infection acquired from ingestion of raw freshwater crustaceans
Adults live& reproduce in lungs, eggs passed in feces & sputum
Disease associated w inflammatory response to excretory/secretory products
Symptoms: chronic cough fever, bronchitis
may resemble pulmonary tuberculosis
diagnostic imaging paragonimiasis
increased alveolar opacity on radiograph
Nodules containing parasites
pleural effusion, pneumothorax
Dx: eggs in sputum, fecal
heterobilharzia americana
canine blood fluke
associated w raccoons
Paired adult worms live in mesenteric (male & female)
granulomatous transport through GI
eggs passed in feces
1 IH (snail)
infection by skin penetration!!
heterobilharzia americana clinical signs
GI signs (vomiting, diarrhea)
polyuria, polydipsia
liver enzymes normal
early dx may improve prognosis
nanophyetus salmicola
salmon poisoning fluke
DH: dogs, cats, fish eating mammals
IH: snail, salmonid fish
acquired by ingestion of metacercaria in kidneys, muscles, &fins of raw salmonid
Zoonotic-> mild GI illness, no Rickettsial
causative agent is Rickettsia!! transovarial transmission
Salmon posioning
hemorrhagic enteritis
clinically indistinguishable from canine parvovirus!!!!!!
Dx: clinical signs and trematode eggs in fecal
platynosomum fastosum
liver poisoning fluke
DH: felines, bile ducts
IH: snail, pill bugs, geckos possible paratenic?
metacercaria ingested when cats eat lizard
-migrate up bile ducts. adult in bile ducts and gallbladder
vomiting, diarrhea, icterus
Dx: clinical signs and trematode eggs in fecal
eurytrema procyonis
raccoon pancreatic fluke
DH: felines, red & grey fox, raccoons
IH: snail, arthropod, possible paratenic
metacercaria ingested by DH
adult worms in pancreatic ducts
-weight loss, vomiting, pancreatitis
alaria sp
IH: snail (1st), tadpole and snake (2nd)
DH: cat, dog
MESOcercaria stage
-larval stage capable of being passed one IH to other
-lactogenic transmission!!
adult stage w/ low pathogenicity in GI
aberrant migration of mesocercaria w adverse effects
Zoonotic potential
fasciola hepatica
liver fluke
DH: cattle, sheep, goats
acquired by ingestion of metacercaria encysted vegetation
cause of liver disease
-anemia, hypoproteinemia, bottle jaw, progressive weakness, loss of condition
fasciola hepatica pathology
fibrosis of liver tissue
hypertrophy of bile ducts
livers condemned @ slaughter
distribution of fascioliasis based on
presence/absence of infected hosts
presence of suitable snail IH
suitable soil that promotes moisture retention (snail habitat)
slope, drainage, water runoff
natural & artificial ponds for watering herd
clorsulon
binds serum proteins and ingested by fluke
inhibits enzymes important in glycolytic enzyme process
not able to extract energy from glucose, disruption of cellular energy production
fascioloides magna
deer liver fluke
DH: white-tailed deer
lifecycle similar to fasicola
adult worms communicate w bile ducts
Non-patent in cattle, sheep, goats (no adult parasite actively reproducing)
Aberrant migration in other ungulate species
-significant tissue destruction
-liver cirrhosis & condemnation @ slaughter
paramphistomum sp
rumen fluke
DH: cattle, sheep, goats
acquired by ingestion og metacercaria encysted on vegetation
adult in stomach, non pathogenic
immature stages in duodenum and ileum pathogenic
-necrosis, hemorrhagic inflammatory disease
-hyproproteinaemia
-diarrhea, dehydration
Dx: clinical signs and eggs on fecal
dicrocoelium dendriticum
lancet liver fluke
DH: cattle, sheep, goats, etc and bile ducts
IH: snail, ants
miracida hatch from egg when ingested by snail, asexual replication, emerge in slime ball
-ingested by ant, infect brain, remain attached to vegetation
-ingested by grazing DH
metacercaria invade entire biliary system within hours
adult in bile ducts and liver
low pathogenicity
Dx: clinical signs and trematode eggs on fecal
parasite infecting respiratory
paragonimus
parasite infecting biliary system
fasciola, fascioloides, platynosum, eurytrema, dicrocoelium
parasite infecting GI
paramphistomum, alaria, nanophytes
prevent trematodes by
breaking the lifecycle
Zoonotic trematodes
paragonimus
nanophytes, no rickettsia in humans!!
alaria
