Injuries to the sole of the foot or feet (abrasion, puncture wounds, bruising, abscess), are commonly associated with excessive wear of moisture-softened feet on rough and abrasive flooring. The conditions are painful and infection of the foot can lead to development of abscessation and sometimes extension of the infection into the interdigital tissue, up the lower leg and into one or more of the joints of the foot.
Cattle that mount other cattle (riders) wear away the front part of the hind claws, and may become lame from bruising and infection. Additional risk factors are temperament of cattle, roughness of handling, concreted laneways with twists and turns, and sharp gravel on concrete yards (carried there on muddy feet).
Foot abscesses in sheep (and goats) usually involve one toe or one heel on one foot and cause acute lameness. Toe abscessation is more frequent in young animals, involves front feet, and may follow horn cracks that provide opportunity for bacteria to penetrate into the foot. Heel abscessation is more frequent in older, heavier animals, involves hind feet and may occur as an extension from interdigital dermatitis into soft tissue at the back of the heel.
In cattle, foot abscesses may occur on any claw but are most common on the outside claws of the hind feet. They are thought to follow damage to the bottom of the foot (sole), and particularly to the white line area (junction between outer hoof wall and the sensitive part of the foot, allowing bacteria to penetrate into the foot. Damage most commonly follows abrasion of the foot on hard surfaces such as rough concrete flooring.
The highest risk groups are generally animals introduced to assembly points from high winter rainfall areas, but sole injuries may be acquired in pens that are muddy and soiled by faeces.
Affected animals are lame or reluctant to move or stand. Closer observation mayl detect swelling of the foot and discolouration of the sole with associated tenderness. Examination is aided by adequate restraint, good lighting, a sharp hoof knife, hoof testers, and double-action hoof cutters.
Cleaning the hoof followed by inspection and application of hoof testers to identify painful areas and then careful paring with a hoof knife will usually allow diagnosis. Sedation with xylazine may be helpful particularly if a crush and head bail are not available.
Animals with foot abscessation are very lame, avoid weight bearing on the affected foot and rapidly lose body condition. The foot is hot and painful on pressure. Toe abscesses may extend to the coronet and heel abscesses will extend up behind the heel. When the abscess is ruptured or opened, usually as one or more sinuses above the coronet, pus is discharged and pain is relieved. If infection has extended to the joint, damage and lameness may be permanent. Foot abscess is distinguishable from the under-run horn found in multiple feet in cases of footrot.
Necropsy of unresponsive cases may find discolouration, pus and foul smelling tissues within the claw, and this may extend up the subcutaneous tissues of the leg.
Cases should be treated early to prevent infection extending up the leg and to prevent the animal becoming a downer or developing other complications as a result of not being able to eat or drink normally. Lame animals are at risk of being smothered, becoming dehydrated, getting other secondary diseases, and developing heat stress if climatic conditions are marginal.
Treat solar abscesses and puncture wounds by paring the sole and wall around the injury to establish drainage. Care should be taken to avoid over trimming or indiscriminate digging with a hoof knife since this may exacerbate lameness and predispose to further injury.
Administration of antibiotics (procaine penicillin) and non-steroidal anti-inflammatory drugs (flunixin meglumine, ketoprofen, meloxicam, or tolfenamic acid) may be helpful. With toe abscesses, paring of the hoof to allow drainage of pus may prevent the need for further antibiotics. Heel abscesses may not drain well when opened and may require a longer course of antibiotics (procaine penicillin, or oxytetracycline) to resolve the infection.
For severely affected cattle and if facilities and expertise are available, consider elevating the inflamed claw by applying a lift to the healthy claw in the form of a plastic shoe or a wooden or plastic block glued to the sole. This will provide dramatic pain relief and help keep the animal on its feet.
Isolate affected animals to provide comfort, ready access to feed and water and ease of monitoring and further treatment. Providing bedding will help to cushion the hoof-ground interface.
Avoid dirty, wet and rough ground conditions. Keep concrete yards free of sharp gravel especially for cattle with soles worn thin. At sea, provide soft, dry, non-slip flooring by distributing plenty of dry absorbent sawdust in pens and preventing water leaks.
Use low stress animal handling methods. Cattle worked on concrete yards over many days must be prevented from overwearing the soles of the feet by being allowed to walk and turn slowly and place feet carefully.
Remove bullers from pens as soon as possible.