Poultry Nematodes Flashcards
What is the name for the poultry gape worm?
Syngamus trachea
What kind of worm is the syngamus trachea?
What birds does it affect?
Where are they found in the bird?
What disease does it cause?
Hookworm
Affects chickens, gamebirds, turkeys
Adult worms in the trachea
Disease- mechanical blockage, asphyxia, coughing
Describe the lifecycle of the poultry gape worm
- Ingestion of L3 eggs, hatched egg or L3 in paratenic host- earthworm
- L3 migrates from SI and enters blood stream
- Larvae reach lung via pulmonary capillaries
- Migrate through alveoli to trachea
- Adults develop in trachea and attach there, males and females in copula (attached)
- Eggs passed in faces, L3 develop in egg
PPP-18-20 days
What species of parasite egg is this from and describe it
Syngamus trachea
Characeteristically shaped- mucoid ends
This worm is very this, 1-5cm long and found in the upper digestive tract or SI
What species is it?
Capillaria spp
How many species of capillaria spp are there?
What kind of life cycles do they have?
What do thier eggs look like?
3 species
Direct and indirect species
Characteristic eggs- barrel shaped with two mucoid plugs
Describe the lifecycle of capillaria spp?
L1 develops in egg
For those with indirect life cycles the intermediate host- earthworm
PPP- 3-4 weeks
Can be highly pathogenic, head of worm deep in mucosa- inappetance weight loss
What different ascarids affect poultry, where are they found and what size are they?
Ascaridia galli- small intestine- 12cm
Heterakis gallinarum- Caeca- 1.5cm
What stage of poultry ascarids is the infective stage?
Where do they develop?
They both have low pathogenicity, why is Heterakis gallinarum a problem?
L2 in egg is infective stage
Develop within the GI tract- no migration
Heterakis gallinarum vector for Histomonas melegridis- highly pathogenic
How are poultry nematodes controlled in housed birds?
Only parasites with direct lifecycles important
Most have resistant eggs
Biosecurity- prevent introduction of nematodes with new batches of birds
Use of in feed BZs (flubendazole)
How are outdoor reared birds poultry nematodes controlled?
Both direct and indirect important
Wild birds important source of infection
Biosecurity- prevent introduction of nematodes with new batches of birds
Use of in feed BZs
Rotate pens between batches of birds
Describe the appearance of histomonas meleagridis
Describe its pathogenesis?
Amoeboid protozoan with single flagellum
Highly pathogenic for turkey poults- ‘black head’
Pathogenesis
Trophozoites (feeding) in caecum erode caecal epithelium
Invade liver causing necrosis and typical saucer like lesions
Clinical signs include depression, ruffled feathers, sulphur yellow faeces
Cyanosis of wattle and comb- black head
How is Histomonas gallinarum controlled?
- Anti-protozoal drug- dimetrazole
- Control relies on good biosecurity
- Control Heterakis infection
- Flubendazole
- Different pens for different batches
- Chickens are asymptomatic carriers- keep away from turkeys
How is Histomonas gallinarum transmitted?
Transmitted by eggs of Heterakis gallinarum
H. gallinarum in caeca and Histomonas also in caeca
H. gallinarum worms ingests Histomonas, which migrate to uterus of female
Incorporated into the H. gallinarum egg
Only transmitted in larvated egg
What protozoa causes watery, bright yellow diarrhoea in young game birds, with direct transmission?
What protozoa causes oral canker, cheesy yellow material around beak from the infection of URT?
Spironucleosis meleagridis
Trichomonas gallinae
