Ascaridia galli

Ascaridia galli

"Ascaridia galli" is a nematode parasite that causes ascaridiasis, a worm infection of poultry.

Life cycle

The eggs of "A. galli" have thick, albuminous shells that are resistant to desiccation and persist for a long time in the environment. Larvae do not hatch but moult inside the eggs until they reach the L3 stage. This can take about two weeks but the period depends on other factors such as the weather condition. The infective eggs are ingested by a chicken where it reaches the proventriculus and hatches. [cite web | title = Helminthiasis: Introduction | work = The Merck Veterinary Manual | date = 2006 | url = http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/202800.htm | accessdate = 2007-07-01 ] Temperature, carbon dioxide levels and pH are thought to be triggering factors that signal the larva to hatch from its egg. The larva then burrows into the mucosal lining of the small intestine where it undergoes two additional moults. It is this phase of their life cycle where these worms causes the most damage to their host. They then re-enter the small intestine and develop into adults where they live their lives out feeding on gut content and making a vast amount of eggs that would then be excreted by a host and free to continue their life cycle. If the animal is able to mount an immune respond to the larvae, i.e. from pre-exposure, the larvae do not develop into adults but hide in the mucosa of the small intestine. This is common for infection of older birds. Transport hosts such as earthworms are thought to play a role in transmission of "A. galli" and hence, free range birds tend to have a higher risk of infection.

References


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Look at other dictionaries:

  • Ascaridia galli — noun intestinal parasite of domestic fowl • Syn: ↑chicken roundworm • Hypernyms: ↑nematode, ↑nematode worm, ↑roundworm • Member Holonyms: ↑Ascaridia, ↑genus Ascaridia …   Useful english dictionary

  • Ascaridia — noun roundworm having a preanal sucker • Syn: ↑genus Ascaridia • Hypernyms: ↑worm genus • Member Holonyms: ↑Ascaridae, ↑family Ascaridae • Member Meronyms: ↑ …   Useful english dictionary

  • Ascaridia — As·ca·rid·ia .as kə rid ē ə n a genus of nematode worms of the family Ascaridae that include an important intestinal parasite (A. galli) of some domestic fowl and esp. the chicken and that are distinguished from other ascarids by the presence of… …   Medical dictionary

  • genus Ascaridia — noun roundworm having a preanal sucker • Syn: ↑Ascaridia • Hypernyms: ↑worm genus • Member Holonyms: ↑Ascaridae, ↑family Ascaridae • Member Meronyms: ↑ …   Useful english dictionary

  • АСКАРИДИОЗЫ — Ascaridia galli. Ascaridia galli: 1 — головной конец; 2—3 — хвостовые концы самца (2) и самки (3); 4 — яйца (а — незрелое, б — с личинкой). аскаридиозы (Ascaridioses), гельминтозы птиц, вызываемые нематодами… …   Ветеринарный энциклопедический словарь

  • chicken roundworm — noun intestinal parasite of domestic fowl • Syn: ↑Ascaridia galli • Hypernyms: ↑nematode, ↑nematode worm, ↑roundworm • Member Holonyms: ↑Ascaridia, ↑genus Ascaridia …   Useful english dictionary

  • Отряд Рабдитиды (Rhabditida) —          Рабдитиды, приспособившиеся к жизни в сапробиотической среде и ставшие участниками круговорота органического материала под главенствующим воздействием сапрофитных бактерий и грибов, стали источником эволюции всего отряда Rhabditida и,… …   Биологическая энциклопедия

  • АСКАРИДИОЗ — инвазионная болезнь птиц (гл. обр. кур), вызываемая нематодами (у кур Ascaridia galli), паразитирующими в тонких кишках. Заражение алиментарным путём . Симптомы: вялость, исхудание, замедление роста и развития, снижение яйценоскости. Лечение;… …   Сельско-хозяйственный энциклопедический словарь

  • ГЕЛЬМИНТОЛОГИЧЕСКИЕ ИССЛЕДОВАНИЯ — Яйца гельминтов. Яйца гельминтов: 1 — Heterakis gallinarum; 2 — Ascaridia galli; 3 — Ganguleterakis dispar; 4 — Syngamus traehea; 5 — Cyathostoma boularti; 6 — Haemonchus contortus; 7 — Bunastomum… …   Ветеринарный энциклопедический словарь

  • nematode worm — noun unsegmented worms with elongated rounded body pointed at both ends; mostly free living but some are parasitic • Syn: ↑nematode, ↑roundworm • Hypernyms: ↑worm • Hyponyms: ↑common roundworm, ↑Ascaris …   Useful english dictionary

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