Ascaridia Galli (Roundworm Large) ...

Ascaridia Galli (Roundworm Large) Heavy Infection in Laying Hens

Happenings / Clinical Signs

  • Most of Ascaridia galli infection is a subclinical condition

Internal Egg contents defects

  • Yolk colour variable
  • Worm inside the egg detected by candling

Ascaridia galli infection causes weight depression in the host, proportionate to increasing worm burden. In severe infections, intestinal blockage can occur. Chicken infected with a large number of ascarids suffer retarded growth, and increased mortality. 

Damage to the intestinal mucosa results in limiting the absorption of carotene  and other micronutrients.

Hens 3 months of age or older manifest considerable resistance to infection with A. galli, regardless of previous infection status. Most of the times Ascaridia galli infection is a subclinical condition

Ascaridia galli can also synergized the effects of other diseases conditions, such as coccidiosis and infectious bronchitis. A. galli reportedly contain and transmit avian reovirus. The infection by this nematode is the occasional finding of this parasite in the hen's egg. Infected eggs can be detected by canding.

The nutritional state of the bird also influence the development of immunity.

Causing Agents
Parasitic intestinal track infection of nematode. Worm parasites. Ascaridia galli.
Affected Systems/Organs
Reproductive system. Intestinal tract.
Fecal-oral Cycle. The parasites may be transported by grasshoppers and earthworms and are resistant to environmental. A. galli reportedly contain and transmit avian reovirus
Mainly Affects
Liveability and egg quality
Removal of droppings from feeders and drinkers and pasture rotation and regular anti-parasite treatment (as locally approved), especially in young birds and Free range production system. The nutritional state of the bird also influence the development of immunity. Diets high in vitamins A and B (complex) increase the fowl's resistance to A. galli. Increasing levels of dietary calcium and lysine decreased the length and number of worms recovered.
Suggested Actions
  • Can be confirmed with clinical signs and gross lesions
  • Technical assistance recommended
  • Can be managed with feed additives, off-the-shelf medications
  • Diagnosis should be confirmed with rapid assays and/or a certified laboratory
  • Veterinary intervention is recommended

Impact on Egg quality


Impact on Liveability


Impact on Production


Overall Economic Impact


Y.M. Saif.2008.Disease of Poultry. 12th Edition.

Mark Pattison, Paul F. McMullin, Janet M. Bradbury. Dennis J. Alexander. 2008. Poultry Diseases. 6th Edition.

Paul McMullin. 2004. A pocket Guide to Poultry Health and Disease. First Edition. page 30

Steven Leeson, John D. Summers. 2008. Commercial Poultry Nutrition. Third Edition.

Donald D. Bell, Williams D. Weaver. 2009.  Commercial Chicken Meat and Egg Production. Fifth Edition.

AVES © 2015                   Privacy Policy | Terms of Use