In recent years multiple dogs of the Old English Sheepdog (OES) breed have been diagnosed with an ocular (eye) disease that can affect multiple parts of the eye and is therefore known as multiocular defect (MOD). Most affected dogs suffer from cataracts, but additional abnormalities can include any of the following:
- microphakia (small lens),
- lens coloboma (a hole in the lens),
- macrophthalmos (enlarged globe),
- retinal detachment,
- vitreopathy and
- retinal degeneration