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Infectious Diseases

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Intestinal Integrity

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Nutritional Health (related to Food Induced Immune Response (FIIR))

β-Mannans: the problem component in soybean meal.
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Worms (helminths)

Worms (helminths)

  • Parasitic worms can affect intestinal and respiratory health, leading to marked effects on poultry health and performance
  • All poultry is at risk of parasitic worm infection: layers, breeders, broilers, turkeys, ducks and geese
  • There is a risk of worms in all production systems, especially free range and floor husbandry as birds are not separated from their droppings
  • Worm eggs can survive in the environment providing a source of infection for birds1, and if no measures are taken to reduce shedding by infected birds, the infection pressure in the environment can increase over time 2

Routes of Infection

Birds can develop infection directly or indirectly, depending on the species of the bird. Direct infection may be caused through the consumption of worm eggs from the floor or pasture or through contact with wild birds. Eggs can also be brought in to a system on food sacks, litter or clothing. This is irrespective of whether the birds are housed or free range. Indirect infection may be caused by consuming intermediate hosts (earthworms, insects, slugs) infected by parasitic worms.

Direct Routes of Infection

Poultry Pictures Poultry routes of infection

Indirect Routes of Infection

Poultry Pictures POULTRY worms cycle

Worm eggs:

  • Require warm, damp conditions to develop
  • Cannot be killed through disinfectants - they can survive for years in the environment
  • Build up in large numbers where there is concentrated use of land by birds (overstocking or little rotation of land), especially if poorly drained.


1Prevalence of gastrointestinal helminths in different poultry production systems, A. Permin , M. Bisgaard , F. Frandsen , M. Pearman , J. Kold & P. Nansen, British Poultry Science 1999; 40: 439-443.
2Genetic differences of Ascaridia galli egg output in laying hens following a single dose infection. Gauly et al. Veterinary Parasitology Vol 103, issues 1-2. Jan 2002, pg 99-107.

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