The Ministry of Agriculture and Forestry is warning farmers that dry dusty conditions can result in outbreaks of pink eye in sheep, particularly when the animals are in close contact.
Pink eye is a type of infectious conjunctivitis that can cause blindness.
The first signs are reddening of the eyes with a watery discharge, and the surface of the eye may then become white. Usually the condition clears up without treatment, but some cases progress to ulceration of the eye and permanent blindness. Usually only one eye is affected, but when both eyes are affected, the animal is unable to see. Ross Burnell of MAF's Animal Welfare Enforcement Unit warns that in areas affected by drought this could prove to be a significant health and welfare issue to add to farmers' problems. Mr Burnell says that supplementary feeding can lead to spread of infection by bringing the heads of the animals into close contact, and dust may cause damage to the surface of the eye and allow infection to gain hold.