Ocular disorders

Chapter 8 Ocular disorders

Congenital disorders

Although by definition congenital abnormalities are present at birth, some may not be recognized until the calf is much older. Strabismus (squint) is a typical example. Congenital disorders may be genetic, and therefore inherited, or they may be caused by environmental factors. Some abnormalities have more than one cause. For example, congenital cataract may be inherited, or it may have been caused by maternal BVD infection during pregnancy. The cause of many abnormalities is unknown. Congenital disorders in organs other than the eye are described in Chapter 1.

BVD/MD, discussed under “Alimentary disorders” (p. 54) can give rise to congenital or acquired ocular changes. Congenital BVD/MD can cause teratogen-induced retinal necrosis and degeneration, focal capsular cataract, as well as optic nerve gliosis, microphthalmos (see below) and optic neuritis. 8.1 shows retinal changes in a calf associated with the teratogenic effects of BVD/MD virus. There is marked attenuation of many retinal blood vessels, retinal hyper-reflectivity and a patchy yellow pigmentary disturbance.

Jul 8, 2016 | Posted by in SUGERY, ORTHOPEDICS & ANESTHESIA | Comments Off on Ocular disorders
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