Other Poultry parasites Flashcards
Name the burrowing mite of poultry
Knemidocoptes spp
How can burrowing mites be distinguished from their appearance?
They have short legs that don’t go beyond the body margins
Name the two non-burrowing mites of poultry
- Dermanyssus gallinae
- Ornithonyssus sylvarum
Dermanyssus gallinae is also known as?
The poultry red mite
How does Dermanyssus gallinae appear?
Appears bright red when fully blood-engorged, grey/black later
What is the significance of Dermanyssus gallinae infections in birds?
- There may be pruritis, papules and crusts on birds
- Birds become debilitated, stop feeding
- Anaemia due to blood feeding habit
- Diagnosis can be difficult because mites are seldom recovered from animals
Ornithonyssus sylvarum is also known as?
The northern fowl mite
How can Ornithonyssus sylvarum be distinguished from Dermanyssus gallium
- Morphologically similar to D. gallinae
- The anal plate is pear-shaped not D-shaped– no point in treating accommodation if only this species is present (ID therefore important)
Describe the morphology of Dermanyssus gallinae
1mm in size
Long legs
D-shaped anal plate
Name two poultry lice
Menacanthus spp
Lipeurus spp
How do poultry affected with lice appear?
Affected birds unable to rest, irritated, body weight decreases, egg production drops
Which species of parasite is the poultry gape worm?
Syngamus trachea
What are some features of Syngamus trachea
- Hookworm
- Affects chickens, gamebirds, turkeys etc.
- Wild bird reservoir
- Adult worms in the trachea
What gives Syngamus trachea the classic ‘Y’ shaped appearance?
Permanently paired worms- the male is constantly inside the female worm inseminating the eggs
What are the disease effects due to Syngamus trachea?
Mechanical blockage of trachea, asphyxia, coughing, and gasping
Describe the life cycle of Syngamus trachea
- Characteristically shaped egg (80um with mucoid end) is passed in faeces
- L3 develops in egg
- Infection via ingestion of: L3 in egg, Hatched L3. L3 in transport/ paratenic host (earthworm)
- L3 migrates from small intestine to lung via bloodstream
- Adults develop in trachea
What is the PPP of Syngamus trachea?
18-20 days
What are the features/appearance of Capillaria spp
- Very thin (capillary-like) worms, 1-5cm long
- Found in the upper digestive tract (crop, oesophagus) or small intestine
- Characteristic eggs (barrel shaped with two mucoid plugs)
Describe the life cycle of Capillaria spp
- L1 develops in egg
- For those with indirect life cycles the intermediate host (earthworm)
- Birds infected by ingesting earthworm
- PPP 3-4 weeks
- Can be highly pathogenic, head of worm buried deep in mucosa leading to diphtheritic inflammation
What are the signs of a Capillaria infection?
Inappetence, weight loss, decreased egg production
Name and describe the poultry ascarid that lives in the small intestine
Ascaridia galli
12cm long
Name and describe the poultry ascarid that lives in the caeca
Heterakis gallinarum
1.5cm long
How are poultry nematodes controlled in housed birds?
- Only parasites with direct lifecycles important
- Most have resistant eggs (Ascaridia, Heterakis and Capillaria)
- Biosecurity: prevent introduction of nematodes with new batches of birds
- Use of in feed BZs (flubendazole)
How are poultry nematodes controlled in outdoor reared birds or birds maintained outdoors?
- Parasites with direct AND indirect lifecycles important
- Resistant eggs and intermediate/transport hosts means parasite stages persist in environment.
- Wild birds important source of infection
- Biosecurity: prevent introduction of nematodes with new batches of birds
- Use of in feed BZs (flubendazole)
- Rotate pens between batches of birds e.g don’t use same pen for different batches of birds when rearing them
Name the highly pathogenic protozoal parasite of turkeys
Histomonas meleagridis
Describe the pathogenesis and disease caused by Histomonas meleagridis
- ‘blackhead’ – severe entero-hepatitis
- High levels of mortality
- Trophozoites in caecum erode caecal epithelium
- Invade liver causing necrosis and typical (pathognomic) saucer-like lesions
What are the clinical signs of Histomonas meleagridis infection
Depression, ruffled feathers, sulphur yellow faeces
Cyanosis of the wattle and comb (hence blackhead)
How is Histomonas meleagridis transmitted?
Transmitted in larvated eggs of Heterakis gallinarum
How is Histomonas meleagridis controlled?
- Control relies on good biosecurity
- Control Heterakis infection – if you get rid of Heterakis you have controlled Histomonas. Flubendazole to control this worm
- Chickens are asymptomatic carriers, so avoid rearing turkeys on ground previously used for chickens
Which parasite is being described?
Young game birds, watery bright yellow diarrhoea. Direct transmission. No treatment. Prevent by all in/all out, mix age groups, rotate pens.
Spironucleosis meleagridis
Which parasite is being described?
Upper respiratory tract of finches, pigeons, birds of prey. Oral canker, cheesy yellow material around beak. Direct transmission. Has led to decline in greenfinches over recent years.
Trichomonas gallinae
