Infectious bovine keratoconjunctivitis (IBK), commonly called pinkeye, is one of the most widespread and painful conditions of beef cattle, causing severe ocular inflammation that can result in permanent blindness without prompt treatment.
IBK causes severe ocular pain that is visually apparent — affected cattle blink constantly, hold the eye partially closed, and strongly avoid bright sunlight. The photophobia of IBK drives cattle to seek shade and disrupts normal grazing and social behaviour. Corneal ulceration is acutely painful, and the rapid progression to blindness in untreated animals removes the ability to navigate the paddock, find water, and avoid dominant pen-mates. Temporary unilateral blindness causes significant distress and makes affected animals vulnerable. Prompt treatment is both welfare-positive and economically rational, as untreated animals lose condition rapidly and may suffer permanent vision impairment.