|
Ophthalmology of birds has become an important part of avian medicine. The principal groups of birds that veterinary ophthalmologists examine in their consultations include cage birds, sport, zoo and wildlife birds. Knowledge on anatomical and physiological peculiarities of the eyes of these species will help in the interpretation of the ocular investigation and in reaching appropriate diagnoses. Some of the most important differences that can be outlined in bird eyes, compared to mammal eyes, include the small ocular size of some species and different morphologies of the eyeball depending on the species. Likewise, the open orbit, voluntary contraction of the pupil (striated sphincter muscle of the iris), ossicles in the sclera, avascular retina and the presence of the pecten protruding into the vitreous chamber (vascular structure that nourishes the retina). Ophthalmic investigation includes a physical ocular examination and complementary techniques, such as tonometry, ophthalmoscopy, electroretinography and ultrasonography, among others, in order to identify the ocular lesions and to evaluate the severity. The most frequent ocular diseases reported include malformations (palpebral agenesia, microphthalmia, cataracts), primary or secondary inflammatory diseases of the eyelids and conjunctiva (poxvirus, chlamydia), trauma (ocular haemorrhages, uveitis, cataracts, chorioretinitis), neoplasms and nutritional disorders (vitamin A deficiency). 
|
