Candidiasis in Waterfowl and Bears (with notes on Elephants, Lagomorphs and Bonobos):

Disease Summary

Alternative Names (Synonyms)

• Candida infection
• Thrush
• Crop mycosis
• Moniliasis
• Sour crop

Disease Type

Infectious/Non-Infectious Agent associated with the Disease

Infective "Taxa"

• Candida spp.
  • Candida albicans

Non-infective agents

Physical agents

References

Disease Author

Referees

Major References / Reviews

Code and Title List

B11.34.w2, B13.35.w2, B15, B16.19.w1, B18, B36.14.w14, B37.x.w1, B48.17.w17
J1.21.w3
J6.7.w2
J7.30.w2
J8.26.w1

In Elephants:

B450.17.w17, B453.7.w7
J354.2.w1
P3.2000b.w1

In Bears:

B10.48.w43, B16.9.w9, B64.26.w5
J4.155.w4
D251.8.w8
P5.29.w5

In Lagomorphs: 

B606.4.w4

In Bonobos & Great Apes
B336.39.w39
J4.157.w8, J23.20.w2
N45.13.w1
R1.18Oct2008.w1

Other References

Code and Title List

Detailed Clinical and Pathological Characteristics

General

Clinical Characteristics

• Gastro-intestinal (usually oral/oesophageal): Anorexia, loss of condition, listlessness, dehydration, 'yeasty' breath. Soft, white to creamy deposits may be visible in the mouth (B11.34.w2, B16.19.w1, B37.x.w1).
• Ocular: Nictitating membrane (third eyelid) thickened, irregular, opaque, grey-white and with a granular external surface. Discrete lesions in mild cases, may become confluent in severe cases. Mild conjunctivitis. Occasionally also focal corneal opacity, and rarely intraocular involvement with associated lacrimation, blepharospasm and photophobia (J6.7.w2).
• Foot: Granulomatous nodule on the plantar surface of one foot, with overlying necrotic skin and associated severe lameness (J8.26.w1).
• Venereal: Penis/cloacal mucosa swollen and reddened, ulcers or granulomatous lesions on the sides of the penis or in the cloaca. Later distal portion (0.5-2cm) of penis blackened, gangrenous and finally sloughing off to leave a shortened penis (J5.17.w1).

• Dermatitis. (B450.17.w17)
  • See: Dermatitis in Elephants
• Hyperkeratosis of the skin. (P3.2000b.w1)
  • See: Hyperkeratosis in Elephants
• Keratitis and corneal ulceration. (J354.2.w1)
  • See: Keratitis and Corneal Ulceration in Elephants

• Death without prior clinical signs, at two weeks old (in a cub hand-reared from five days old). (J4.155.w4)

• A moist dermatitis can occur due to infection with Candida albicans. The chin and dewlap are the most likely areas to be affected. (B606.4.w4)

• Oral candidiasis was seen in two recently imported two-year-old bonobos at Yerkes, USA, with severe stomatitis in one of the bonobos. The bonobos, which were refusing to eat, were emaciated and died due to Klebsiella pneumonia. (J23.20.w2, N45.13.w1)
• Oral candidiasis was seen in a hand-reared bonobo, with typical signs. Intermittent/recurring over a period of about four weeks. (R1.18Oct.w1)
• Anorexia, diarrhoea and dehydration were seen in a one-year-old Pan troglodytes - Chimpanzee. (J4.157.w8)
• Tongue lesions were seen in a Gorilla gorilla - Gorilla. (J26.19.w2)

Incubation

Mortality / Morbidity

• Candidiasis waspersent but not considered to be the main cause of death in two two-year-old female bonobos recently imported to Yerkes, USA.  (J23.20.w2)

Pathology

• Gastro-intestinal (usually oral/oesophageal): White to cream, cheesy plaques in the mouth and oesophagus. Inflamed, thickened surrounding mucosa (J7.30.w2, B11.34.w2, B37.x.w1, B48.17.w17). (N.B. Similar lesions occasionally seen affecting the proventriculus, cloaca, respiratory tracts, skin (B37.x.w1).)
• Gastric: Budding yeast-like organisms (3-4µm diameter) and masses of pseudohyphae on the surface of the koilin layer and extending into the koilin. Positive staining with Periodic Acid-Schiff (J1.21.w3).
• Ocular: Pseudomycelial hyphae, blastospores and chlamydospores in the nictitating membrane and (if involved) the cornea and deeper parts of the eye. Superficial erosion of the keratinised layers of the nictitating membrane, the stratum spinosum infiltrated with hyphae and budding blastospores. Also some oedema, spongiosis and early acanthosis. Mild corneal oedema, and cellular infiltration: heterophils and mononuclear cells (J6.7.w2).
• Foot: Granulomatous mass, mainly granulation tissue, with necrotic fibrous tissue, heterophils and scattered granulomas in the dermis, totally destroyed epidermis. Fungal elements (hyphae and yeasts) detected in necrotic outer dermis, blastosporulated yeasts in granulomas (J8.26.w1).
• Venereal: Inflammatory foci in penis and cloaca, mild to severe inflammation, with variable numbers of fungal elements; also mixed bacteria. Glands in cloaca blocked with fungi (J5.17.w1).

In a two week old Ursus maritimus - Polar bear cub:

• Skin: Single puncture (probably bite) caudal to the left scapula. 
• Mouth: tongue and corners of the mouth covered with adherent white material.
• Stomach. Distended. Extending from the greater to the lesser curvature, a 1-inch-wide (2.5 cm) band of ischaemic tissue, with intensely hyperaemic edges and gastric mucosa
• Bladder: multiple small congested areas of the mucosa.
• CNS: Over the left tentorium cerebelli, extending for 1 cm over the cerebellum, a piece of white material. In the lateral third and fourth ventricles, similar material filling the ventricles. 

  (J4.155.w4)

Histopathology

In a two week old Ursus maritimus - Polar bear cub:

• Mouth: Dorsum of the tongue hyperkeratotic and parakeratotic. Septate pseudohyphae were found penetrating the stratum corneum and numerous bacterial colonies were present in the superficial keratin. (J4.155.w4)
• GIT: Stomach - large infarct, with an intensely congested border containing a massive lymphocyte infiltration. In the submucosa were bacterial rods. (J4.155.w4)
• CNS: Within the cerebral ventricles, extensive occlusive fibrinopurulent exudate. Choroid plexuses swollen with infiltration of leucocytes and fibrin accumulation. Also ependymitis and adjacent non-purulent encephalitis and congestion of adjacent vessels. In the infiltrate were mainly lymphocytes but also in some areas poylmorphonuclear leucocytes and macrophages. No pathogenic microorganisms were detected. (J4.155.w4)

Gross pathology

In a one-year-old Pan troglodytes - Chimpanzee: (J4.157.w8)

• GIT: Oesophageal mucosa covered in a yellow-white, tenacious pseudomembrane. (J4.157.w8)

Histopathology

In a one-year-old Pan troglodytes - Chimpanzee: (J4.157.w8)

• GIT: Superficial oesophagel epithelium necrotic. Adjacetnt to normal epithelium, numerous pseudohyphae and blastospores, and at the interface with the normal epithelium, macrophages and large lymphocytes. (J4.157.w8)

Human Health Considerations

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

• Long-tailed duck Clangula hyemalis, Barrow's goldeneye Bucephala islandica, common scoter Melanitta nigra, red-breasted merganser Mergus serrator (J6.7.w2).
• Domestic geese (J5.17.w1).
• Geese (B48.17.w17).
• 'Swans'. (B15)
• 'Seaducks' in the UK (J7.30.w2).
• Mute swan Cygnus olor (J8.26.w1)

In Elephants:

• A case of Candida albicans infection has been reported in an elephant (species not specified). (B453.7.w7)
• Candida albicans infection has been detected in an Elephas maximus - Asian Elephant associated with hyperkeratosis of the skin. (P3.2000b.w1)
• Candida spp. are among the infectious agents commonly found associated with dermatitis in elephants. (B450.17.w17)
• A Candida sp. yeast was isolated together with bacterial infection from the eye of an Elephas maximus - Asian Elephant with ocular lesions in Sri Lanka. (J354.2.w1)

In Bears:

• Gastroenteric and encephalitic candidiasis infection has been reported in bears (species not specified). (B10.48.w43)
• Candida albicans affecting the oral cavity, oesophagus and stomach was reported in a two week old Ursus maritimus - Polar bear cub. The infection appeared after a four day course of prophylactic erythromycin. (B16.9.w9, B64.26.w5, J4.155.w4)
• Candidiasis was the primary diagnosis in three Kodiak bear (Ursus arctos - Brown bear) cubs of 20 aged four to seven months which died at Rostock Zoo, 1971-1985, and was a secondary finding in a further eight cubs. (P5.29.w5)
• Thrush developed in a young Ursus maritimus - Polar bear cub being hand-reared at Brookfield Zoo in 1999-2000. (D251.8.w8)

In Lagomorphs:

• A moist dermatitis can occur in domestic rabbits (Oryctolagus cuniculus domesticus) due to infection with Candida albicans. (B606.4.w4)

In Bonobos:

• Oral candidiasis in a bonobo being hand-reared at Twycross Zoo. (R1.18Oct2008.w1)

Host Species List

• Bucephala islandica - Barrow's goldeneye
• Clangula hyemalis - Long-tailed duck
• Cygnus olor - Mute swan
• Melanitta nigra - Black scoter
• Mergus serrator - Red-breasted merganser

MAMMALS:

• Bears (Ursidae - Bears (Family))
  • Ursus arctos - Brown bear
  • Ursus maritimus - Polar bear
• Elephants (Elephantidae - Elephants (Family))
  • Elephas maximus - Asian Elephant
• Lagomorphs (Lagomorpha - Lagomorphs (Order))
  • Oryctolagus cuniculus domesticus - Domestic European rabbit
• Primates (Primates - Primates (Order))
  • Pan paniscus - Bonobo

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

Host Species List

General Information on Environmental Factors/Events and Seasonality

• No seasonal aspects, except that incidence may be higher in spring and summer due to the presence of juveniles which may be more susceptible. Overcrowding and unsanitary conditions may be predisposing factors.
  (B36.14.w14, B37.x.w1, B48.17.w17).

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

Similar Diseases (Differential Diagnosis)

Preventative Measures

WATERFOWL

• Treatment and Care
• Preventative Medicine for Birds
• Preventative Medicine for Mammals

Environmental and Population Control Measures

WATERFOWL

• Preventative Medicine for Birds
• Environmental and Population Management
• Preventative Medicine for Mammals