Plant-Induced Photosensitization (Primary) in Waterfowl

Disease Summary

Alternative Names (Synonyms)

• Phytophotodermatitis
• Plant-Induced Photosensitisation

Disease Type

Infectious/Non-Infectious Agent associated with the Disease

• Contact Plant Toxins: Heracleum mantegazzianum - Giant Hogweed contains furocoumarins and Hypericum perforatum Common St. John's Wort contains hypericin; on external skin contact, these toxins may sensitize the skin to sunlight.
• Systemic Plant Toxins: Ammi visnaga, Ammi majus - Bishop's weed, Cymopterus watsonii (syn. Cymopterus ibapensis), Cymopterus longipes, Petroselium sativum - Parsley (syn. Petroselium crispum), and Hypericum spp. berries have all been reported to contain various systemic toxins that have been responsible for photosensitization after ingestion and absorbtion. Hypericin may also act systemically after ingestion.
• Ultra-violet radiation (e.g. sunlight) is required to trigger photosensitization.

(B101, B103 )

Infective "Taxa"

• Ammi majus - Large bullwort
• Ammi visnaga - Toothpickweed
• Cymopterus ibapensis - Ibapah springparsley
• Cymopterus longipes - Longstalk springparsley
• Heracleum mantegazzianum - Giant Hogweed
• Hypericum spp.
• Hypericum perforatum - Common St. Johnswort
• Petroselinum crispum - Parsley

Non-infective agents

• Photosensitizing Toxins (Systemic)

Physical agents

• Radiation - Sunlight (UV Radiation)

References

Disease Author

Major References / Reviews

Code and Title List

Other References

Code and Title List

Detailed Clinical and Pathological Characteristics

General

Clinical Characteristics

• Eyes - lachrymation, conjunctivitis, blepharitis, protrusion of third eyelid, inflammation of periorbital skin, loss of feathers around eyes. Eye may become sealed by serous exudate, may develop to purulent blepharo-conjunctivitis.
• Bill - Erythema (reddening) of dorsal bill, diffuse inflammation, development of fluid-filled vesicles or blisters, haematomata and scabbing. Vesicles may be sufficiently large to obstruct nares and cause open-billed breathing. Bill lesions not seen with pigmented bills in the case with Heracleum mantegazzianum - Giant hogweed (J3.116.w1).
• Feet and legs - Usually most severe on dorsal surface of footwebs. Erythema, inflammation, vesicles or blisters, which may rupture, scabbing. Erythema, oedema and pruritis of legs.

SUB-ACUTE / CHRONIC DISEASE (Usually systemic):

• Eyes - Ankylo-blepharon with partial or total closure of the eyes, cicatrical ectropion, eccentric pupil position, irregular pupil shape and mydriasis, pigment retinopathy, periorbital baldness -sometimes more extensive across head.
• Bill - Scabbing, scarring, maxillary bill shorter than mandibular bill, with sides and/or tip turned up. Lesions were noted on pigmented bills of goslings with Ammi major, which caused severe signs in both ducklings and goslings (J3.97.w1, J5.18.w1, J5.19.w1, J6.3.w1).
• Feet and legs - Footwebs thickened and cicatrized, occasionally holes in footwebs, occasionally deformities of phalanges, skin of legs scared and thickened, occasionally carpal joint thickened and twisted. Only leg lesions noted with Hypericum spp. berries (B11.35.w3).
• Stunting (both acute and chronic) was noted with Cymopterus longipes at high doses (2g/kg body weight) (J5.22.w1).
• Only leg lesions noted with Hypericum spp. berries (B11.35.w3).

(J3.97.w1, J3.166.w1, J5.18.w1, J5.19.w1, J5.19.w2, J5.22.w1, J6.3.w1, J6.17.w1, B11.35.w3).

N.B. Lesions varied in severity.

Incubation

Mortality / Morbidity

• Morbidity of 48% noted with accidental consumption of Ammi majus in goslings (J5.19.w1). One death from liver failure with Hypericum spp. berries (B11.35.w3). One death from 2g/kg body weight Cymopterus longipes in ducklings (J5.22.w1).
• Ammi visnaga was noted not to produce lesions in goslings but was considered to affect ducks, although no lesions were seen when fed experimentally to ducklings as 6% of the diet (J5.4.w1, J5.18.w1).

Pathology

• Gross Pathology: Liver - yellow and friable (with Ammi major).
• Histopathology: Liver - degenerative changes: diffuse parenchymal necrosis, fatty infiltration of hepatocytes.
• Clinical pathology: Decreased serum albumin (All with Ammi major in goslings)

N.B. Lack of liver pathology specifically noted with Petroselium sativum - parsley in ducklings

(J6.17.w1).

Human Health Considerations

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

• Ducklings and goslings.

Host Species List

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

Host Species List

General Information on Environmental Factors/Events and Seasonality

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

• History and Documentation - General
• Physical Examination - General
• Necropsy - General
• Environmental Assessment - General
• Chapter 2 - B36 Field Manual of Wildlife Diseases - Specimen Collection and Preservation
• Chapter 3 - B36 Field Manual of Wildlife Diseases - Specimen shipment
• Appendix A - B36 Field Manual of Wildlife Diseases - Sample specimen history form

Similar Diseases (Differential Diagnosis)

Specific Medical Treatment

• Treatment and Care - General

General Nursing and Surgical Techniques

• Treatment and Care - General

Preventative Measures

WATERFOWL

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Environmental and Population Control Measures

WATERFOWL

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