HORSE TOPICS
By Lars Rahmquist

The particularly wet winter presents number of foot issues for your horse. Constantly standing in wet muddy conditions predisposes the hoof to a number of ailments. Much like when you've been in the bath for too long (if that's possible) and your fingers go all wrinkly; the horney tissues of the hoof become ‘macerated'. The horney layer of the hoof is made up of the same tissue type as that of your fingers, namely keratin. So, on a much lesser scale the horn tissue becomes soft and (very slightly) folded. This means that there is a compromise to the natural defence mechanisms of the hoof wall. I will touch on a few conditions that this can lead to.

•  Foot and toe abscesses.

The compromised horney tissues become less resistant to bacterial invasion. This can come via the smallest of holes that may be created when the soft sole steps on something sharp and hard. It can also occur through clinch tracts via the white line (the white circumference around the wall of the foot); this is usually the way toe abscesses form.

When shoes are removed during sodden conditions, the horn tissue around the clinch lines can be too weak to resist colonisation by opportunistic bacteria.

Horse will go particularly lame very quickly with foot abscesses.

A skilled practitioner must cut out the abscess, making sure that the hole left is large enough to not close back over and have the abscess reform. A poultice or ionic (salt) bandage can be placed to aid in (osmotically) drawing out inflammatory fluid. It can be very difficult keeping foot bandages on in wet conditions and the use of hoof boots is particularly helpful in these circumstances.

The bacteria which cause these infections are generally always penicillin sensitive, so a 3-5 day course of penicillin injections aids in the rapid recovery from foot abscesses.

The final and possibly most important point to note is that the environment of these infections is perfect for the colonisation of Clostridium tetani. Animal species vary greatly to the effects of the tetanus poison. Horses are considered the most sensitive to the tetanus condition. It causes complete rigidity of all muscles in the body and horses which contract it need to be euthanized.

Horses need to be vaccinated annually against tetanus to have sufficient antibodies to stop the diseases taking hold. Portugal does not stock tetanus antitoxin, an injection to mop up the poison in unvaccinated horses. This makes it doubly important to make sure your horses tetanus vaccination status is up to dat.

•  Sole bruises

As the horney tissue of the sole soften they become less resistant to blunt trauma. When there's mud everywhere it's hard for your horse to avoid ‘submerged' stones. Put the two together and a sole bruise will soon ensue. Solar bruises tend to occur towards the sides of the foot. Cleaning away the sole, one can often see a tinge of red underneath the surface of the sole (unless the horn is black, of course).

Horses tend not go quite so lame from this as from an abscess.

Hooves can be hardened by various chemicals. We make a preparation which contains formalin for such purposes. Painted on daily it cross links the collagen in the hoof wall to harden the horney tissues.

•  White line infections

These are infections that spread up the white line from the bottom of the foot and can spread write up to the pastern, occasionally bursting out over the coronet band. Veterinary attention is needed to resolve these infections.

Regular checking of the bottom of the foot (once scrubbed clean) can help catch these conditions early.

•  Mud fever/thrush

Although not technically an infection of the hoof, this condition is caused by infection into macerated tissues under wet conditions (namely the back of the foot).

It can cause lameness to a lesser degree.

Regular cleaning with iodine can resolve superficial infections, but a course of penicillin injections is needed in advanced cases.

For any questions about hoof care, you can contact VIP Veterinary Clinic in Lagos.