Hoof care
Hoof care is an important aspect of sheep management. Hooves
should be regularly checked for disease and excess growth.
Hoof Trimming
Hoof growth is affected by the breed and genetics of the sheep,
soil moisture, and soil characteristics. Sheep grazed on rocky,
dry soil may not require the extent of hoof care needed for sheep
on soil that is free of rocks and higher in moisture content.
Sheep in high rainfall areas will need to have their hooves inspected
more regularly than those on dry ground. How often will depend
on the specific conditions.
Proper footrot or foot paring shears are essential to doing
the job properly. The ordinary, manual shears are not expensive
and make the task so much easier. Air compressor driven shears
are an option for people with large numbers of sheep. A sharp
paring knife is needed to remove pockets and do a more thorough job of hof trimming.
Foot paring can be back-breaking work if there are a lot of
sheeps feet to pare. There are various types of sheep
handling equipment that can hold the sheep in a
good position so that the stress on the person paring can be
reduced. However, for small numbers of sheep, it is usually
enough to tip the sheep up and sit it on its rump, as you would
for crutching.
Securely hold the leg of the sheep. Inspect the hoof and remove
any mud, manure, or small stones between the walls of the hoof.
A rotten smell is usually indicative of foot rot. Clean all
the junk and crud out of the hoof using a knife or the point of the shears.
After cleaning the hoof, begin trimming around the perimeter
of the hoof.
Avoid cutting off large chunks of hoof. Stop at the first sign
of pinkness. A pink color means you are getting close to the
foot blood supply. The foot should be trimmed from the heel
to the toe to remove excess growth of the "horny"
portion of the hoof. To learn what a properly trimmed hoof look
like, study the feet of a newborn lamb. Its hooves are flat
on the bottom and have a boxy look.
When trimming feet, avoid stressful times such as hot weather
or late gestation. It's a good idea to combine hoof trimming
with other management tasks, such as shearing or deworming.
It will be easier to trim hooves that are soft from heavy dew
or rain.
Diseases Affecting the Hoof
You should never ignore lameness in sheep. Lameness is a sign
of several foot conditions some of which are very serious
as well as some other problems. They include:
Bluetongue
Foot lesions occur in some animals with bluetongue, an arthropod-borne
virus. A red to brown band around the coronet is an important
diagnostic sign of bluetongue.
Foot Abscess
This disease is characterized by a swelling of the soft tissues
immediately above the hoof and in advanced cases, draining abscesses
in this area and between the toes. Foot absceses are caused
by bacterial infection of damaged foot tissue. The front feet
are most commonly affected. Treatment is with anti-bacterial
compounds.
Foot and Mouth Disease (FMD)
Foot and mouth disease is a highly contagious viral disease
that affects pigs, cattle, sheep, goats, and deer. It is endemic
in many parts of the world. Clinical signs of the disease in
infected animals include blisters or ulcerations on the mouth,
snout, tongue, gums, teats, or around the top of the feet. The
signs of FMD in sheep and goats are usually much less obvious
than in cattle or pigs.
The United States has eradicated nine outbreaks of FMD, the
last of which occurred in 1929. Since then, no cases have ever
been reported in the United States. Canada has been free of
foot-and-mouth disease since 1929. The United Kingdom experienced
a foot-and-mouth outbreak in 2001.
Foot Rot
Foot rot is one of the most devastating diseases in the U.S.
sheep industry. It is caused by a synergistic action of two
anaerobic bacteria, along with environmental conditions conducive
to their growth and spread. The bacteria are Fusobacterium
necrophorum and Bacterioides nodusus.
F. Necrophorum is commonly present in soil and manure.
It is the B. Nodusus organism, when present, that causes
the problem. Again, both bacteria have to be present to cause
footrot. There are over 20 strains of the B. Nodusus bacteria,
varying in their infectivity and severity.
Warmth, mud and poor sanitation are environmental conditions
that also favor footrot spread. these conditions create the
anaerobic (lack of oxygen) conditions necessary for the spread
of the disease. The B. Nodusus organism will only live
in soil for 14 to 21 days.
The bacteria that causes foot rot, Bacteriodes nodosus,
is spread from infected sheep to the ground, manure, bedding,
etc., where it is then picked up by noninfected sheep. Foot
rot is introduced by purchase of an infected animal or by simply
using facilities or trucks that have been contaminated by infected
sheep.
Spread occurs best when temperatures are from 40-70°F and
the environment is wet. Since the organism doesn't survive long
in the environment (< 2 wks), carriers in the flock will
continue to reinfect the flock unless the animal is either culled
or the organism is eliminated by proper treatment.
Treatment of foot rot should be approached from a flock standpoint.
Since the footrot organism is anaerobic, the introduction of
oxygen to its environment will help in eradicating it. Thus,
it is important to keep sheep's hoofs trimmed. Elimination of
overgrown hoof tissue will result in less mud and manure packing,
which aids in environmental conditions conducive to footrot
development. After foot trimming, the use of regular soaking
in a footbath of a zinc sulfate solution (10% w/v) can greatly
help in eradicating the disease.
Vaccination of flocks with a history of footrot can help in
prevention and in treatment of current cases. However, just
because a sheep is vaccinated for footrot does not mean it is
immune to infection. The vaccine does not cover all the strains
of footrot. Producers with clean flocks can control footrot
more economically by prevention rather than vaccination. Antibiotics
can also be used to help treat cases of footrot. Penicillin
can be particularly effective on a short-term basis.
Severely infected sheep that do not respond to treatment should
be culled. There can be a genetic susceptibility to footrot;
some sheep are more susceptible to footrot than others. Also,
there can be breed differences in susceptibility to footrot.
British and European breeds are less susceptible to footrot.
Thus, sheep that have a resistance to footrot should be propagated,
while, susceptible animals should be culled. Keeping records
can help in identification of these types. Generally, black-pigmented
hooves are hardier than white-colored hooves.It is much easier to prevent foot rot than to eradicate it.
Several management practices help to minimize the chances that
foot rot will establish itself in a flock. You should never
buy sheep infected with foot rot. Avoid buying apparently clean
sheep from an infected flock. Avoid buying sheep from sale barns
where clean and infected sheep are penned together.
Assume all new additions to your flock are infected with foot
rot. Always isolate new animals for at least two weeks. Trim
feet immediately upon arrival. Treat feet of new sheep following
trimming. Re-inspect feet during the quarantine period.
Foot Scald (interdigital dematitis)
Foot scald is an infection of only F. necrophorum and is
not contagious. Foot scald causes lameness, frequently on the
front feet, and lesions are found between the hooves. The tissue
between the toes of a sheep with foot scald are generally blanched
and white, or red and swollen. Foot scald is much easier to treat
than foot rot. Many times, placing sheep on drier footing and
out of mud will alleviate the problems of the disease.
Foot scald may also be treated topically by applying a solution
of copper sulfate (Kopertox). The simplest and most effective
treatment is use of a footbath containing 10% zinc sulfate solution
(8 pounds zinc sulfate to 10 gallons water). The frequency and
severity of foot scald infection will decline as drier weather
returns.
Laminitis (founder)
Lameness related to laminitis is caused by inadequate blood flow
in the hoof caused by digestive problems resulting from the excessive
intake of grain (grain overload, acidosis). Animals often die
before the feet become involved. Recovered animals may exhibit
unusual foot growth and/or permanent lameness.
Soremouth (contagious ecthyma)
Lameness caused by soremouth is the result of blisters appearing
on the skin near the top of the hoof wall. Simultaneous blisters
appear on the mouth and other areas of the sheep's body. The
infection is more common around the mouth than on the legs or
feet. Lesions can be treated with an ointment containing a broad
spectrum antibiotic. Soremouth can be prevented with vaccination.
<== SHEEP 201 INDEX