Wet-Feather in Waterfowl

Disease Summary

Alternative Names (Synonyms)

• Shaft-lice Infection
• Sooty Mould Exposure

Disease Type

Infectious/Non-Infectious Agent associated with the Disease

• Shaft louse or biting louse Holomenopon leucoxanthom (B10.26.w11, B11.35.w3, B13.46.w1, B46, J8.17.w1, P4.1992.w1)
• Mould spores e.g. Cladasporum herbarum - sooty mould, from Osier willows (B11.35.w3, V.w3).
• Also:

• lack of water to bathe in
• soiling of feathers with mud or droppings, or from dirty/dusty bedding
• contamination of plumage with oil or surfactants
• physical damage to feathers

(B11.35.w3, B95, D214.2.w2, J2.12.w2)

Infective "Taxa"

• Holomenopon leucoxanthum - Shaft louse
• Cladosporium herbarum - Sooty mould

Non-infective agents

• Oil
• Soaps
• Synthetic Detergents

Physical agents

• Soil and mud
• Surface tension of water decreased by surfactants
• Faecal - Urine contamination of substrate

References

Disease Author

Major References / Reviews

Code and Title List

Other References

Code and Title List

Detailed Clinical and Pathological Characteristics

General

Clinical Characteristics

• Plumage tatty, dirty, broken, waterlogged.
• Excessive preening - may be continuous, particularly with lice, due to irritation, or decreased with severe debility.
• Bird may become wet through to the skin and chilled; pneumonia is a possible consequence.
• Loss of waterproofing and buoyancy may lead to drowning

(B10.26.w11, B11.35.w3, B13.46.w1, B37.x.w1, B46, B95, J3.97.w3, J8.17.w1).

Incubation

Mortality / Morbidity

Pathology

• Plumage damaged and wet; feathers may be broken and barbules disrupted.

• Shaft louse (Holomenopon leucoxanthum) infection: Preen gland may be reddened and dysfunctional Small (1-2mm) lice may be found on the feather shafts within the feather follicles (J3.97.w3, B37.x.w1, B46).
• Sooty mould - black dust visible on feathers; more easily seen in birds with pale plumage (V.w3).
• Preen gland dysfunction: preen gland may be inflamed with e.g. bacterial infection, or may be inactive.
• Detergent contamination: feather structure is normal (but lowered surface tension of water allows the water to penetrate the barbules). (J2.12.w2)

Human Health Considerations

Disease has been reported in either the wild or in captivity in:

• Andean crested duck - Lophonetta (Anas) specularioides alticola - Holomenopon leucoxanthum infection, UK (J3.97.w3)
• White-backed duck Thalassornis leuconotus (J7.33.w3)
• Northern goose or geese (J7.34.w1).
• Swan(s) (J7.43.w1)
• 'Sawbills' (J7.30.w2)
• Ducks (with Holomenopon) (B46).
• Swans, snow geese Anser caerulescens, Chiloe wigeon Anas sibilatrix, Puna teal Anas puna and other species with sooty mould (V.w3).

Host Species List

• Anas puna - Puna teal
• Anas specularioides - Crested duck
• Anas sibilatrix - Chiloe wigeon
• Anser caerulescens - Snow goose
• Thalassornis leuconotus - White-backed duck

Disease has been specifically reported in Free-ranging populations of:

Host Species List

General Information on Environmental Factors/Events and Seasonality

• Cladosporium herbarum - sooty mould, is associated with Osier willows Salix viminalis. Mould is reduced by severe winters and may become more of a problem following mild winters (B11.35.w3, V.w3).
• Soiling with mud or droppings, and excessive dust, are generally associated with poor environment, bad hygiene and overcrowding.
• Soiling with faeces can also occur in highly aquatic birds being maintained on land, for example while being treated for oiling. (D214.2.w2)
• Oiling is associated with environmental contamination with oil.

(B11.35.w3).

Regions / Countries where the Infectious Agent or Disease has been recorded

Regions / Countries where the Infectious Agent or Disease has been recorded in Free-ranging populations

General Information on Investigation / Diagnosis

• Holomenopon leucoxanthom: presence of small, rapidly-moving louse, on feather shafts (more likely to be visible if feather plucked) and particularly around preen gland; preen gland inactive (J3.97.w3, B37.x.w1, B46). N.B. lice may be present asymptomatically in small numbers on healthy birds (B11.35.w3).
• Cladasporum herbarum: presence of osier willows (Salix viminalis), presence of mould visible on the trees and/or on the affected bird. N.B. mould may not be easy to see on dark plumage (B11.35.w3, V.w3).
• Presence of oil, mud or other contaminant, poor environment, lack of water for bathing (B11.35.w3).
• Widespread physical damage to feathers (B11.35.w3).

• History and Documentation - General
• Physical Examination - General
• Environmental Assessment - General
• Necropsy - General
• Appendix A - B36 Field Manual of Wildlife Diseases - Sample specimen history form

Similar Diseases (Differential Diagnosis)

See also Feather Lice Infection, Chilling / Hypothermia, Oiling.

Specific Medical Treatment

• For Holomenopon leucoxanthom: dust with topical 'louse powder' - malathion or carbamate, two treatments 14 days apart. Care not to leave excess powder on the bird in case of ingestion and possible toxicity (B10.26.w11, B13.46.w1, B37.x.w1, B46, J8.17.w1).
• N.B. avoid 'oily' preparations which may interfere with waterproofing (B11.35.w3, B37.x.w1).

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General Nursing and Surgical Techniques

• Remove from unhygienic or contaminated environment.
• Wash to remove oil, mud or other contaminants.
• Provide water to encourage bathing after gross contamination has been removed, or when lack of water for bathing has stopped the bird from preening. N.B. take care as a waterlogged bird may drown even in very shallow (few centimetres deep) water.
• Lightly spraying with water may encourage preening in a depressed bird.
• Return to normal environment only when waterproofing has returned. N.B. this may not occur until after the next moult.

(B11.35.w3, B95).

• Treatment and Care - General

Preventative Measures

WATERFOWL

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Environmental and Population Control Measures

WATERFOWL

• Avoid development of excessively muddy or faecal-contaminated environment.
• Remove Salix viminalis - osier willows, or keep birds away from the trees.

(B11.35.w3).

• Environmental and Population Management - General
• Accommodation Design for Birds - General