Metastrongylus

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Metastrongylus

Metastrongylus sp. under the microscope

Kingdom:	Animalia
Phylum:	Nematoda
Class:	Secernentea
Order:	Strongylida
Family:	Metastrongylidae
Genus:	Metastrongylus

Species

M. elongatus (Dujardin, 1845) syn. M. apri
M. pudentodectus (Wostokow, 1905)
M. salmi (Gedoelst, 1823)
M. confusus (Jansen, 1964)
M. asymmetricus (Noda, 1973)

Metastrongylus is a genus of nematodes of the family Metastrongylidae, usually found as lungworms in pigs and sometimes causing verminous bronchitis. It causes a disease called metastrongylosis.

[edit] Species

Metastrongylus elongatus (Dujardin, 1845) syn. M. apri
Metastrongylus pudentodectus (Wostokow, 1905)
Metastrongylus salmi (Gedoelst, 1823)
Metastrongylus confusus (Jansen, 1964)
Metastrongylus asymmetricus (Noda, 1973)

[edit] Life cycle

Life cycle of Metastrongylus sp.

The life cycle is indirect. The eggs are laid by the adult worm in the bronchi. They are coughed up, swallowed and passed out via the feces. The eggs are then eaten by earthworms in which they develop through three larval stages over ten days to become infective. The cycle is completed by the pig eating the earthworm. Infection therefore only occurs where pigs have access to earthworms, for example in outdoor production.^[1] The larvae from the earth worm penetrate the intestine and migrate via the lymph nodes and blood vessels to the lungs undergoing two more larval stages in the process. The prepatent period is 3-4 weeks.