Changes

Adult ''A. galli'' are semi-transparent, have three prominent lips in their oral openings and are the '''biggest nematodes found in poultry'''. Females range from 72 to 116 mm in length and their reproductive organ opens in the middle of the body. Their eggs are oval, with smooth shells and measure 73-92 by 45-57 µm and are distinguished from [[Heterakis#Heterakis gallinarum|

Adult ''A. galli'' are semi-transparent, have three prominent lips in their oral openings and are the '''biggest nematodes found in poultry'''. Females range from 72 to 116 mm in length and their reproductive organ opens in the middle of the body. Their eggs are oval, with smooth shells and measure 73-92 by 45-57 µm and are distinguished from [[Heterakis#Heterakis gallinarum|

''H. gallinarum'']] eggs  by their slightly smaller and parallel sides (Soulsby, 1982). Males vary from 51 to 76 mm in length and they have pre-anal suckers and two equal spicules of 1-2.4 mm long.  

''H. gallinarum'']] eggs  by their slightly smaller and parallel sides <ref name="Soulsby">Soulsby EJL (1982) '''Helminths, arthropods and protozoa of domesticated animals. ''Helminths, arthropods and protozoa of domesticated animals''., Ed. 7:xi + 809 pp.44; [many fig., 260 x 195 mm]; many ref.</ref>. Males vary from 51 to 76 mm in length and they have pre-anal suckers and two equal spicules of 1-2.4 mm long.  

Compared to  ''A. galli,  A. dissimilis'' is slightly bigger and ''A. columbae'' is slightly smaller.   

Compared to  ''A. galli,  A. dissimilis'' is slightly bigger and ''A. columbae'' is slightly smaller.   

Infected chickens '''pass''''' A. galli'' eggs in their '''faeces'''. The '''larvae develop inside the egg''' until they reach their '''infective stage (L3)''' within 10-20 days or more, depending on environmental temperature and humidity. The embryonated egg can survive a winter with moderate frost and remain infective in deep litter systems for years depending on the temperature, humidity, pH and ammonium concentration.

Infected chickens '''pass''''' A. galli'' eggs in their '''faeces'''. The '''larvae develop inside the egg''' until they reach their '''infective stage (L3)''' within 10-20 days or more, depending on environmental temperature and humidity. The embryonated egg can survive a winter with moderate frost and remain infective in deep litter systems for years depending on the temperature, humidity, pH and ammonium concentration.

''Ascaridia galli'' has a '''direct lifecycle''' and it is complete when a new host (another chicken) ingests the infective embryonated eggs (L3) from contaminated water or feed. Three layers around the egg protect the larvae until it reaches the duodenum/ jejunum, where they hatch within 24hrs and enter the '''histotropic phase'''. They '''embed themselves into the mucosal layer of the intestine'''. The more eggs are present the longer the histotropic phase lasts. The length of this stage before the final maturation has been reported to be between 3 to 54 days (Herd and McNaught, 1975). The '''prepatent period''' varies from '''5 to 8 weeks'''.

''Ascaridia galli'' has a '''direct lifecycle''' and it is complete when a new host (another chicken) ingests the infective embryonated eggs (L3) from contaminated water or feed. Three layers around the egg protect the larvae until it reaches the duodenum/ jejunum, where they hatch within 24hrs and enter the '''histotropic phase'''. They '''embed themselves into the mucosal layer of the intestine'''. The more eggs are present the longer the histotropic phase lasts. The length of this stage before the final maturation has been reported to be between 3 to 54 days <ref name="Herd and McNaught">Herd RP, McNaught DJ (1975) '''Arrested development and the histotropic phase of Ascaridia galli in the chicken''''' ,International Journal for Parasitology '', 5: 401-406</ref>. The '''prepatent period''' varies from '''5 to 8 weeks'''.

Adult ''A. galli'' worms may migrate through the lumina of the large intestine and cloaca and end up in the oviduct, where they can be incorporated into the hen’s egg. Occasionally, earthworms can ingest ''A. galli'' eggs and ascarids are transmitted when the chicken ingests the worm.   

Adult ''A. galli'' worms may migrate through the lumina of the large intestine and cloaca and end up in the oviduct, where they can be incorporated into the hen’s egg. Occasionally, earthworms can ingest ''A. galli'' eggs and ascarids are transmitted when the chicken ingests the worm.   

The life cycles of ''A. dissimilis'' and ''A. columbae'' are also direct and ''A. dissimilis'' may migrate through the liver (Norton et al., 1999).

The life cycles of ''A. dissimilis'' and ''A. columbae'' are also direct and ''A. dissimilis'' may migrate through the liver <ref name="Norton et al.">Norton RA, Clark FD, Beasley JN (1999) '''An outbreak of histomoniasis in turkeys infected with a moderate level of Ascaridia dissimilis but no Heterakis gallinarum.''''' Avian Diseases'', 43(2):342-8</ref>.

==Diagnosis==

==Diagnosis==

==Treatment==

==Treatment==

'''In feed''' treatment with '''piperazine salts, levamisole''' or a '''benzimidazole'''.<ref name="Veterinary Parasitology"> Taylor, M.A., Coop, R.L., Wall, R.L., (2007)'''Parasites of poultry and gamebirds''' in: ''Veterinary Parasitology (third edition)'', 467-468.</ref>

'''In feed''' treatment with '''piperazine salts, levamisole''' or a '''benzimidazole'''.<ref name="Veterinary Parasitology"> Taylor, M.A., Coop, R.L., Wall, R.L., (2007) '''Parasites of poultry and gamebirds''' in: ''Veterinary Parasitology (third edition)'', 467-468.</ref>

==Control==

==Control==