Infectious bovine keratoconjunctivitis (pinkeye or IBK) is a painful bacterial eye disease of cattle causing corneal ulceration, temporary or permanent blindness, and significant welfare impact in affected herds.
Pinkeye causes genuine acute suffering from eye pain and photophobia — cattle with active corneal ulceration show reduced feeding, isolation, and head-lowering to avoid light. The pain is significant enough to affect weight gain and production. The corneal opacity itself — if it progresses to permanent scarring or perforation — causes lasting visual impairment that affects the animal's ability to navigate, find feed, and avoid social threats. Early treatment is highly effective and inexpensive; the welfare cost of delayed treatment is disproportionately high. Routine monitoring for early signs, face fly control, and prompt treatment are the most important welfare interventions for IBK.