WHITE LINE DISEASE 

an excerpt from:  

Sole Ulcers, White Line Disease, and Infectious Claw disorders:  Primary Causes of Lameness in dairy Cattle

By Dr. Jan Shearer DVM, MS University of Florida

Areas of hemorrhage and necrosis of the corium are often most noticeable and severe in the white line region of the sole.  this corresponds to the weight-bearing region of the claw.  Because it is an active area of hoof formation it is highly vascular, and a frequent site for hemorrhage during bouts of laminitis.  These areas of hemorrhage are not visible during the acute stage for laminitis.  Instead, they gradually rise to the surface of the sole over a period of weeks.  At this point they become visible and useful as indicators of disease of the corium (subclinical laminitis).

Another outcome of veterinary significance associated with laminar necrosis is the formation of subsolar abscesses (otherwise known as white line disease).   Most of these abscesses are sterile but nonetheless troublesome as they cause acute lameness in affected animals.  However, abscesses tend to occur at higher incidences in animals suffering laminitis via another mechanism - penetration of the white line by foreign material from the environment.  There are a couple of reasons for this: 1) dermal-epidermal separation and distorted claw growth which results in widening of the white line, and 2) hoof horn formed by the diseased corium is softer and thus more subject to wear and penetration by foreign material from the environment.  As a consequence, the incidence of white line disease increases in herds suffering laminitis.

Regardless of how the abscess develops, it is treated by paring and drainage.  For abscesses which develop as a result of penetration through the white line or sole, establishing drainage through the original site of the contaminant's entry is the desired approach when possible.  The site of entry can usually be visualized as a dark area packed with extraneous debris on the surface of the sole.  Visibility of these is often improved following cleaning and/or paring away of the superficial layers of the solear horn.  Once the entry site is located careful paring out of the tract leading to the abscess is required until drainage is accomplished.  Care should be taken to establish drainage, however minimize peripheral damage.  The hoof wall adjacent to the abcessed area should be pared away so that weight-bearing is minimized at this site.  Furthermore, removal of the wall adjacent to the abscess prevents extraneous material from being packed into the solar defect created by paring to establish drainage.  All undermined and loose horn associated with the abscess should be removed.  Many animals will show immediate improvement, whereas others in which abscessation was more extensive may take several days to improve.  there is no need for antibiotic  therapy unless the infection extends to deeper tissues of the foot as evidenced by swelling and severe lameness.

This article is a reprint from 

ROCHE ANIMAL NUTRITION AND HEALTH 

Dairy Nutrition Technical Workshop

 August 21,1998 

 DANA POINT, CALIFORNIA, USA