|
Building a Foundation Foot Care in Foals
Stephen E. O'Grady, DVM, MRCVS
Among the many factors that dictate the
success of the foal as a sales yearling or a mature athlete
are decisions and management concerning feet and limbs during
the first four months of life. This is the time when hoof care
helps to produce a foundation for his/her future athletic
career while influencing the growth and angulation of the limb
above the hoof.
Many leading breeding farms have developed foot care programs
that utilize the skills of a veterinarian with an interest in
podiatry and a farrier working together as a team. The
veterinarian uses his medical and anatomical knowledge while
the farrier utilizes his technical and mechanical background.
This joint venture allows a faster and more accurate
diagnosis, treatment and prognosis of foot problems. Problem
or suspect foals are examined on a monthly basis and followed
through weaning. Many subtle problems can be detected early,
leading to immediate correction. If this program corrects the
limb or increases the athletic potential of one animal, then
it becomes cost effective. The major drawback with this type
of program is that it can be time consuming.
Evaluating the Foal
Good record keeping is very important. Records are designed
for the individual needs of the farm and should reflect the
physical appearance of a foal's limbs and feet at birth and
all minute changes that occur with development. Foals should
be observed walking each time they are trimmed. I prefer to
observe the foal walking before I examine the feet and limbs.
Watching the young foal walk is difficult as they seldom walk
straight toward you. A suggestion would be to walk the mare
along a fence or wall and let the foal follow. Observe the
foal as it walks toward you and as it walks away from you.
What we are looking for here is any lameness that may be
present, the arc of the foot flight pattern, how the foot
breaks over at the toe and especially, how the foot contacts
the ground. When examining the feet and limbs, an imaginary
dot system works nicely. Starting at the ground surface of the
foot, an imaginary dot is placed on the toe, coronary band,
fetlock, top of cannon bone, carpus (knee), top of carpus and
top of forearm.
When these dots are connected with an imaginary line, it is
easy to see if and/or where a deformity exists. In the ideal
situation, the dots should form a straight line. However, one
must be careful to rule out the presence of a rotational
deformity. In this case, both knees face outward leading to a
toe out or splay-footed conformation, yet when the dots are
connected they form a straight line. Next the coronary band is
observed to see if it is level or parallel with the ground (a
good indication of balance), the hoof/pastern angle is noted
from the side to determine if it is aligned and not broken
forward (flexure deformity) or broken backward. Any swellings
along the limb or involving the joints are noted and recorded.
Each deformity is noted and scored on a scale of 1-5. Grade
one is very mild whereas grade five is severe. The above
examination enables us to evaluate the feet, limbs and
movement in a systematic manner.
Trimming the Foal
In the first few months of life, more attention should be
directed toward the structural integrity of the foot (foot
mass) rather than to cosmetics. The important factors here are
to promote the growth of thick, durable hoof wall, to ensure
maximum sole depth in order to protect the tender, vulnerable
white line and developing third phalanx (coffin bone) and to
establish a strong heel base. Keeping in mind that mass of
foot--which is defined as strong hoof wall, adequate sole
depth and a solid heel base--is vital for future soundness,
very little horn wall should be removed from these foals in
the first few months. It is the author's opinion that a hoof
pick and a rasp are the only tools needed to trim foals that
are kept on a monthly schedule. By having the foal walk
entirely on the hoof wall, the hoof wall is consistently
loaded which makes it become thicker and more durable. This is
achieved by not removing as much hoof wall length from the
foal and allowing the margin of the horn wall to project just
beyond the sole. Young foals that are trimmed frequently and
very short develop thin fragile hoof walls.
My method of trimming foals may differ from the traditional
but it is efficient and my results have been extremely
rewarding over the years. The foot is cleaned with a hoof pick
and only loose, shedding areas of the frog are removed.
Otherwise, the frog is left untouched. The unaltered frog acts
as a protective mechanism because it has the ability to absorb
and dissipate concussive forces better. Moreover, it is felt
by many that by leaving the frog intact, the proper width
between the heels will be maintained. The surface of the frog
should be level with or below the heels of the hoof wall, not
above them. Trimming the heels lower than the frog so that the
frog projects above them for the purpose of creating frog
pressure, does not keep the heels wide, may lead to bruising
and is in no way beneficial. In like manner, no sole is
removed from the foal's foot with a hoof knife. The sole in a
foal is extremely thin and all the protection possible is
needed to protect the immature developing structures above.
Removing sole is a primary cause of bruising in foals and can
lead to flexural deformities (contracted tendons) as a result
of the pain. On many farms that have continued problems with
upright hoof angles and clubfeet, the problem can be traced to
their trimming practices. The health of the foot throughout
the animal's life is based on a good solid heel base. The heel
base includes the hoof wall at the heel, the bars (which
together form the angle of the sole) and a nice wide frog. The
bars are needed for support and to establish this strong heel
base. The heels are trimmed flat and the hoof wall at the toe
and quarters is then lowered as necessary using a rasp placed
at a 90o angle just in front of the white line.
When the desired amount of hoof wall is removed, the outer
sharp edge of the angle is removed by running the rasp around
the anterior portion of the hoof thus creating a nice rounded
edge. This will help to prevent cracks and chips in the hoof
wall. This method of using the rasp also leaves the hoof wall
a little higher than the sole causing the hoof wall alone to
bear the bulk of the weight when the animal moves. This
stimulates the wall to grow thicker and become stronger (foot
mass). From our earlier examinations, our objective is balance
i.e. that the foal's foot lands flat. If the foal's foot does
not contact the ground evenly, we may want to adjust the
anterior-posterior balance (front to back) or the lateral to
medial balance (side to side). If one lowers the inside or
outside wall past balance (level), it should not be any more
than 2-3 millimeters at one time. Trimming at two-week
intervals may be useful in this situation.
The age-old theory of lowering a toed-out foal on the outside
and lowering a toed-in foal on the inside may be harmful
rather than beneficial. The cause of the foal turning in or
out is rarely in the foot. The problem is generally a
conformational deformity in the structures above the foot;
therefore, when you lower one side of the foot past balance,
you distort the hoof capsule, place abnormal pressure on the
growth plates and overload the joints on the side that is
being lowered. This can be proven radiographically a few days
after trimming. This is why the initial examination is so
important to determine where the deviation originates. Foals
are born with a hoof angle of up to 60o. There does
not appear to be any reason why we have to be in a hurry to
lower the heels unless a conformational fault exists. The heel
is trimmed with a rasp until the outer wall and the bar are
above or level with the frog. Again, our objective from the
start is to create foot mass-strong hoof wall, depth of sole
and a good heel base.
I recommend starting to trim foals at one month of age. All
that may be necessary at this time is to square the toe to
force the foal to break over in the center of the foot. Many
foals at this age may break over on the outside or the inside
of the toe.
Rotational deformities are very common, especially among
narrow-chested foals. The leg alignment is correct in these
cases but the entire limb is rotated outward; therefore it is
a positional defect rather than an angular defect. As the foal
moves, it is quite noticeable that the outside hoof wall of
the foot lands first. These foals should be trimmed level and
not have their feet lowered on the outside wall. In cases
where the inside heel has been driven upward due to impact
(sheared heels), we lower the inside hoof wall slightly.
Corrective trimming does not offer favorable results in the
malpositioned limb, as this deformity must be corrected in
flight and to date, no form of therapy offers this feature.
Therefore, maintain balance (keep level), be patient and
encourage chest development through exercise. As the chest
fills out, the elbows are pushed outward, rotating the limb
inward.
|
Related Articles
|
|
