SA Metastrongyles Flashcards
Name four species of metastrogyles which can affect dogs and cats.
- Angiostrongylus vasorum
- Crenosoma vulpis
- Oslerus osleri
- Aelurostrongylus abstrusus
Where in the body would adult Angiostrongylus vasorum be found?
Pulmonary arteries and right heart chambers
How big would a Angiostrongylus vasorum be?
2cm
Describe the morphology of adult Angiostrongylus vasorum.
Barber pole - reproductive and GI systems intertwine. Dorsal notch
Name the intermediate hosts of Angiostrongylus vasorum.
Molluscs - slugs - Arion rufus
Outline the lifecycle of Angiostrongylus vasorum.
Eggs hatch in the dogs lungs and are released into the pulmonary vessels they moult to L1, these are coughed up and swallowed. L1 are passed in the faeces and taken up by the intermediate host, which is then eaten by the dog. Larvae mature and to adults which migrate to the heart.
What is the PPP of Angiostrongylus vasorum?
5-8 weeks
Outline the migratory route of Angiostrongylus vasorum.
Migrates via blood, lymph, heart and pulmonary arteries
How long do A. vasorum larvae spend in the intermediate host?
17 days
How is A. vasorum transmitted to the definitive host?
L1-L3 in the slug or possibly free L3
Name a minor paratenic host of A. vasorum.
Frog
Outline the clinical signs associated with A. vasorum infection.
Respiratory - exercise intolerence, lethergy, soft moist cough, dyspnoea. Coagulopathies Fluctuating Haematoma Neuro Wt loss
Which group of dogs are at higher risk of A. vasorum infection?
Young - up to 10 months
Radiographic signs of A. vasorum include…
Patchy alveolar and interstitial pattern Cardiomegaly Enlarged pulmonary artery Need to differentiate from other lung worms via BAL and faecal examination
How can A. vasorum infection be diagnosed?
BAL Faecal examination Antigen blood test Radiography Clinical signs
Outline the treatment and control of A. vasorum.
Milbemycin oxime MOX, FBZ Corticosteroids Prophylactic anthelmintics Reduce exposure to fox and slug habitats
Describe the morphology of Crenosoma vulpis.
Slender white worms 1.5cm Spiny cuticular folds
Where can Crenosoma vulpis be found in the dog?
Mucus of trachea, bronchi and bronchioles
Name two species of metastrongyle, on with a direct and one with an indirect lifecycle.
Direct - Oslerus osleri, Indirect - Angiostrongylus vasorum
Where would adult Oslerus osleri be found in the definitive host?
In nodules in the trachea (particularly the tracheal bifurcation
How is Oslerus osleri transmitted between dogs?
Through the faecal-oral route Through sputum - such as bitch grooming puppies
What is the PPP of Oslerus osleri?
10-18 weeks
How can Oslerus osleri infection be diagnosed?
Bronchoscopy to visualise nodules Larvae in faeces (low sensitivity)
What clinical signs would be suggest Oslerus osleri infection?
Respiratory signs due to obstructive nodules - chronic cought, tracheo-bronchitis, exercise intolerence.
What characteristic feature characterises Aelurostrongylus abstrusus?
S-shaped tail of L1 larvae
Birds and mice act as paratenic hosts of which metastrongyle?
Aelurostrongylus abstrusus
What clinical signs are assocaited with A. abstrusus?
Usually asymptomatic but can cause coughing and respiratory disease.
What treatment would be used in an A. abstrusus infection?
FBZ
