Superfamily Metastrongyloidea Flashcards
What are the general features of Metastrongyloidea?
Mouth small / absent
Bursa small
Direct / indirect lifecycle
Found in respiratory / circulatory system
What is the general metastrongyloidea lifecycle?
Eggs or larvae passed in faeces
Indirect lifecycle –> intermediate host is gastropods (snails / slugs) or earthworms. Carry the L1-3 and are ingested by the IH and then they are ingested by the DH (small ruminants, pigs, cats, dogs)
Direct lifecycle –> L1 infects the host (dogs)
What species infect Pigs?
Metastrongylus apri
What species infects sheep / goats
Protostongylus refescens
Mullerius capillaris
Cystocaulus oreactus
What species infect dogs
Oslerus olseri
Angiostongylus vascorum
Angiostrongylus cantonesis
What species infect cats
Aelurostongylus abstrucsus
What are the main features of the Genus Metastrongylus. Give a species
Infect pigs - Metastrongylus apri
Located in the trachea, bronchi and bronchioles
Have 3 lips
Spicules are long and transversely striated
Eggs are embryonated and have a corrugated surface
Indirect lifecycle –> females lay eggs in respiratory tract, are swallowed. Exits in faeces as L1 within egg and ingested by earthworms. Pigs infected by ingestion of earthworms
What are the features of the metastrongyloidea that infect sheep / goats
Located in the small bronchioles, terminal bronchioles and alveoli
3 species
Indirect lifecycle –> females produce eggs that hatch in lungs, L1 is shed in faeces. L1 invades molluscs (snails/slugs). Develop to L3 within IH, sheep / goats become infected via ingestion of the IH on pasture that contain L3. Molluscs are digested and L3 released, travel to trachea via intestine to liver to heart to lungs.
What is the main features of Oslerus Osleri?
Infect dogs - wild dogs and dingoes
Located in nodules at the junction of the trachea and bronchi.
Males have no bursa
Females tail is rounded and blunt
Long worms
No development occurs outside the host
L1 is located within saliva or faeces –> transmission via saliva from mum to pup when cleaning
Regutitation of food transmission
L1 is infective stage so they have autoinfection
What are the main features of Angiostongylus vascorum?
Host is dog and fox
Located in the pulmonary artery in the R side of the heart
red worms
Contain IH of snails and slugs
L1 shed in faeces
DH become infected by ingestion of gastropods that contain L1, slime or the paratenic hosts
What is the main routes of transmission for Angiostrongylus vascorum?
Ingestion of gastropods containing L1
Ingestion of paratenic hosts containing L1
Ingestion of food contaminated with slime from infected gastropods
What is the name of the parasite that has the intermediate host of snails and slugs and is located in the pulmonary artery and R side of the heart?
Angiostrongylus vascorum?
What are the main features of angiostrongylus cantonesis?
DH are rats
Adults are located in the pulmonary arteries of the DH
IH = slugs, snails
Paratenic hosts = dogs, horses, humans
Larvae are located in the brain of IH and Paratenic hosts
L3 can be eliminated from the IH via slime but will contaminate the soil and plants –> can be ingested with food and water (infects the paratenic hosts)
L1 = infectious stage pasted in faeces, IH = molts to L3, moves to the DH
What are the routes of infection of Angiostrongylus cantonensis?
Ingestion of infected IH
L3 eliminated from mucous and slime onto soil / plants –> contaiminate food / water, ingested
Ingestion of paratenic hosts
What species of parasite infects the brain and spinal cord of the paratenic and intermediate hosts?
Angiostrongylus cantonesis
