Mycobacterial keratitis in a parrot

Area of Science:

• Avian pathology and veterinary ophthalmology.
• Comparative pathology and infectious diseases.
• Microbiology and wildlife health.

Background:

• Avian tuberculosis, caused by Mycobacterium species, can lead to disseminated disease in birds.
• Ocular manifestations of avian tuberculosis are rare, making diagnosis challenging.
• The third eyelid plays a crucial role in ocular health and protection.

Observation:

• Histologic examination of a Maximilian's Parrot revealed acid-fast organisms within a corneal granulomatous lesion.
• The parrot presented with an unexplained corneal lesion despite antemortem diagnostic efforts.
• Disseminated mycobacteriosis was confirmed as the underlying systemic condition.

Findings:

• Acid-fast bacilli were identified as the causative agents of the corneal granuloma.
• A dysfunctional third eyelid was suspected as the initiating factor for the corneal lesion.
• This case highlights an uncommon presentation of ocular involvement in avian tuberculosis.

Implications:

• This finding expands the understanding of Mycobacterium's impact on avian ocular tissues.
• It underscores the importance of considering disseminated mycobacteriosis in birds with unusual ocular signs.
• Further research into avian ocular disease mechanisms and the role of the third eyelid is warranted.