The most common form is caused by M bovis bacteria. This usually occurs November onwards.

Predisposing factors: dust flies seed heads / thistles

It is spread mainly by flies.

Signs: Initially just weeping eyes that shut due to sunlight sensitivity. This progresses to a small white centre where the ulcer is forming.

Eventually the whole eye is involved

Treatment:

Eye ointments Covering with patches LA alamycin

In severe outbreaks whole herd treatment with LA Alamycin twice two days apart can stop the continuing spread. Use eye ointment and patches on top of this for severe cases.

You can use Piliguard vaccine to protect calves.

There is a second form of pink eye that occurs out of season and usually during the early spring in calves. It is caused by M. bovoculi and is extremely contagious and spreads rapidly through calves.

It responds better to LA alamycin injections and patching. You can diagnose with a swab culture.

A vaccine can be made from your culture for future use.