WHITE LINE DISEASE

White line disease is a condition of the hoof wall in which the hoof wall separates from the underlying laminae (stratum internum) at the level of the stratum medium (tubular horn) of the hoof wall.

CAUSES


Infections – both fungal and bacterial organisms have been isolated from affected feet. They are more likely to be secondary invaders than the primary cause.


Mechanical – increased separating forces can be caused by long toes, poor conformation and hoof imbalances. Pre-existing damage will increase susceptibility e.g. from chronic laminitis.


Nutritional – poor quality horn due to deficiencies or imbalances in diet.


Environmental – wet, unhygienic conditions soften the horn, allowing penetration of bacteria. Conversely, excessively dry hooves are prone to cracks and fissures allowing bacteria to enter.


CLINICAL SIGNS


Dry crumbling horn at the white line and blackened areas, depending on the type of infection involved.
The ground surface of the hoof wall will become undermined and ragged and prone to splitting off.
Nailing on shoes will become a problem. As the separation progresses up the hoof wall it may sound hollow when tapped.
Lameness will become apparent when the separation becomes more extensive and there is a strain put on the remaining attachments between the hoof wall and the sensitive laminae




TREATMENT AND CONTROL:


Removal of abnormal horn; specialist shoeing to stabilise the hoof; topical medical treatments e.g. 2% iodine to disinfect affected horn; nutritional supplementation with biotin, lysine, calcium and trace elements to help improve the quality of new horn growth; keeping the feet clean and dry.
The treatments required and duration of the recovery will depend on the severity of the case.
Successful treatment can depend on sometimes radical and extensive removal of the hoof wall. This will take time to regrow.
Acrylic hoof repair products may be used once all infection is gone.


Reference


https://www.severnedgevets.co.uk/wp-content/uploads/2015/02/XLEquine-Factsheet-25-White-Line-Disease.pdf