Bovine- Dictyocaulus, Taenia, Fasciola, Fascioloides Flashcards
What is Dictyocaulus spp. Common name?
lung worm
What is Dictyocaulus spp. Identification?
Adults: long (8 cm), thin, in bronchi
Infective stage: L3
Diagnostic stage: L1 Baermann
What is Dictyocaulus spp. ( D. arnfieldi )
Adapted to donkeys; clinical signs rare
Rarely patent in horses; cough / can be highly pathogenic
What is Dictyocaulus viviparus Common name?
lung worm
What is Dictyocaulus viviparus Hosts?
cattle
What is Dictyocaulus viviparus Identification?
Adults – slender white worms (8 cm) in trachea and bronchi
L1– in feces
What is Dictyocaulus viviparus Life cycle?
Adult females pass eggs which
hatch to L1
L1 coughed up and pass in feces
L1 develop to L3, migrate up herbage (or dispersed by fungi)
L3 ingested; migrate from intestine via blood to lungs; mature
PPP: 24 d
What is Dictyocaulus viviparus Pathogenesis Penetration phase?
Days 1-7
Larval migration
Clinical signs not apparent
What is Dictyocaulus viviparus Pathogenesis Prepatent phase?
Days 8-24
Larvae develop to adults in lungs
Alveolitis and bronchitis
What is Dictyocaulus viviparus Pathogenesis Patent phase?
Days 25-60
Presence of adult worms in lungs
Bronchitis and pneumonia
What is Dictyocaulus viviparus Pathogenesis Postpatent phase?
Days 61-90
If animal survives, recovery starts
Relapse can occur; entire lungs diseased
What is Dictyocaulus viviparus Clinical signs?
Bouts of coughing at rest
Postpatent parasitic bronchitis
dissolution and aspiration of dead or dying worms at end of infection
What is Dictyocaulus viviparus Diagnosis?
Clinical signs History Endemic area Identification of L1 Necropsy
What is Dictyocaulus viviparus Treatment and prevention?
Anthelmintics
Management
Vaccine (Europe)
What is Taenia spp. (characteristics?)
Taeniid egg
Adults in small intestine
Adults largely non-pathogenic
What is Taenia saginata Common name?
Beef tapeworm
Pearly beef
What is Taenia saginata Hosts?
final host – human
intermediate host – bovine
What is Taenia saginata Identification?
8 m long unarmed scolex
Egg taeniid
What is Taenia saginata Site(s) of infection?
Final host – small intestine
Intermediate host – striated muscle
What is Taenia saginata Pathogenesis, lesions, clinical signs?
Final host – discomfort with passing of segments
IM – none except when heavy infections with cysticerci in heart.
What is Taenia saginata Diagnosis (cattle)?
Meat inspection
Serology – antigen-ELISA or antibody tests
What is Taenia saginata Treatment and prevention?
(Bovine) Praziquantel highly effective, but expensive for large animals Dissemination of information (Humans) Cook meat Freeze meat Hygiene
What are Trematodes Identification?
Adults: leaf shaped, dorso-ventrally flattened, hermaphroditic
What is Trematodes Intermediate host?
Snail
What is Trematodes Diagnostic stage?
operculated egg (brown)
What is Fasciola hepatica Hosts?
Final hosts – cattle, sheep, goats, other ruminants and humans
Intermediate hosts – snails (lamenaid??)
What is Fasciola hepatica Identification?
Adults – 3 cm; leaf shaped
Eggs – characteristic; 130 μm
What is Fasciola hepatica Site(s) of infection?
bile ducts of liver
What is Fasciola hepatica Pathogenesis, lesions, clinical signs?
Immature flukes migrate and feed; fibrosis replaces necrotic tracts
Adults consume blood, irritate host, cause “pipestem liver”
Chronic fasciolosis associated with mature flukes in bile ducts
What is Fasciola hepatica Diagnosis?
Quantitative sedimentation
ELISA bulk milk
Elevated globulin, elevated albumin, elevated GGT
What is Fasciola hepatica Treatment and prevention?
Some flukicides available
Snail control and management
What is Fascioloides magna Common name?
large American liver fluke deer fluke
What is Fascioloides magna Hosts?
Definitive hosts – white tailed deer, wapiti, caribou, etc.
Dead-end hosts – cattle, moose, sika deer and bison
Aberrant hosts – sheep, goats and roe deer
Intermediate hosts – snails
What is Fascioloides magna Identification?
Adults – 10 cm; large; oval
Eggs – distinct; 130 μm
What is Fascioloides magna Site(s) of infection?
adults in liver
What is Fascioloides magna Life cycle?
Similar to F. hepatica, but juvenile flukes wander aimlessly, destroy liver tissue
What is Fascioloides magna Life cycle: Definitive host (deer etc.)?
cyst forms around fluke, develop to adults which lay eggs
What is Fascioloides magna Life cycle: Dead-end host (cattle etc.)?
cyst encapsulates fluke in liver, never patent
What is Fascioloides magna Life cycle: Aberrant host (sheep, goats etc)?
fluke migrates, no cyst forms, animal dies before patency
What is Fascioloides magna Pathogenesis and lesions/Clinical signs: Deer and cattle?
parasite encapsulated by host minimizes clinical effects
What is Fascioloides magna Pathogenesis and lesions/Clinical signs: Sheep and goats?
continuous migration of immature flukes results in death before patent infection
What is Fascioloides magna Diagnosis?
Definitive hosts – eggs detected
Dead-end and aberrant hosts – eggs not detected
What is Fascioloides magna Treatment and prevention?
Economic losses of cattle livers
Anthelmintics effective, but not approved in USA
Snail control
in areas where deer are natural reservoir, the land may be unusable for grazing of deer and livestock together
