The primary cause of pink eye is infections by bacteria such as *Moraxella bovis*. These bacteria often enter the eye through abrasions or irritation caused by factors like dust, UV light, and other environmental stressors. Certain breeds, especially those with lighter pigmentation around their eyes, are more predisposed to this condition. Other predisposing factors include high stocking density, poor ventilation, and excessive flies, which can transmit bacteria.
