Avian Digestive System Disorders

Chapter 172 Avian Digestive System Disorders


General Principles

Bacterial and Mycotic Infection

Superficial or deep bacterial and mycotic infections occasionally are seen. These usually are secondary to trauma, chronic rhinitis, or other systemic diseases. Gram-negative enteric organisms (e.g., Pseudomonas, Escherichia coli, and Klebsiella species) are the most common bacteria isolated. Aspergillus fumigatus is the mycotic agent most commonly identified. In budgerigars, Knemidokoptes mite infestation is the most common infectious cause of beak deformity.


Beak damage from trauma can occur in all species and often is the result of aggressive behavior among individual birds housed together, flying into walls or windows, struggling after beak entrapment, or improper beak trimming. A split lower beak may result from a fall, injury from another bird, biting with excessive force, or beak trimming.


Treatment varies with the type of injury. If the bird is reluctant to eat, forced alimentation may be necessary until the beak has healed sufficiently.


Normal Structure and Function

Hypovitaminosis A

Hypovitaminosis A, which is generally the result of an unsupplemented, all-seed diet, causes squamous metaplasia of the oral epithelium and subsequent hyperkeratosis of the mucous glands. Keratin-filled cystic structures may be found on the palatine folds, base of the tongue, laryngeal prominence, and pharynx. These lesions may coalesce and become secondarily infected to form large abscesses.

Lesions are more likely to be seen in large psittacine birds (e.g., Amazon and African grey parrots, macaws, and cockatoos) than in small species (e.g., budgerigars and cockatiels).

Psittacine Pox

See Chapter 169 in this section for discussion of this disorder.

Oral Candidiasis

Candida albicans is a secondary invader that affects the mouth, esophagus, and crop. Factors predisposing to oral candidiasis include poor sanitation, malnutrition, coexisting disease, and prolonged antibiotic therapy. Cockatiels and macaws are affected most commonly.

Aug 27, 2016 | Posted by in SMALL ANIMAL | Comments Off on Avian Digestive System Disorders

Full access? Get Clinical Tree

Get Clinical Tree app for offline access