New Forest Eye

New Forest eye is often seen at this time of year as the bacteria which causes it is spread by flies. Affected cattle are commonly found with tears overflowing and running down their faces – causing a wet or sticky patch below the eye, and often the eye is squinting or being held shut due to pain.  

If we can examine the eye more closely then there are a few features that may be seen:

• An ulcer (wound) on the surface of the eye  
• Cloudy surface of the eye – the cornea 
• A pink ring between the edge of the eyeball and the white of the eye 

The bacteria which cause this condition is called Moraxella Bovis and has a special ability to attach to the surface of the eye with miniscule hairs on the surface of its cell, it then releases tissue damaging enzymes and toxins that break down the normal eye surface tissue and allow the bacterial infection to take hold. 

Treatment is via antibiotics which can be given into the eye using a cream, or an injection into the muscle which is then excreted into the tears thus delivering antibiotics to the surface of the eye, in some cases your vet may recommend an injection into the eye tissues. Damage to the eye is painful and so a combined pain relief and anti-inflammatory injection is recommended, as if we reduce pain then this also makes it less likely the cow will try and rub the eye which always makes matters worse. It is useful to house any affected cattle, as direct sunlight can make the eye more painful until healing has occurred. 

Fly prevention should always be discussed as a control strategy – for example pour on skin preparations containing deltamethrin will reduce the number of flies on the cattle, but also if possible limiting grazing of cattle near to fly breeding habitats such as wet muddy areas and dung heaps can also be helpful.