Foot scald, also referred to
as benign foot rot or interdigital dermatitis, is an inflammation
between the toes caused by F. necrophorum. Persistent moisture
on the skin between the toes can increase susceptibility to
foot scald. However, foot scald does not seem to be contagious.
A significant proportion of the herd will likely show signs
of the disease under ideal environmental conditions. Foot
scald often precedes hoof rot.
Foot scald and foot rot outbreaks occur most
often during persistent rainy weather along with high temperatures,
when animals walk across wet pastures and muddy soil. If not
treated, these animals can become permanently infected. During
the rainy season, infected animals can contaminate the soil,
which can increase disease transmission to other animals.
Overgrown hooves will also predispose an animal to foot scald
or rot. The disease causes stress to the animals and can affect
weight gain, reproductive rates, and wool production. Foot
rot and scald may incur additional costs for treatment and
increased labor during an outbreak.
Introducing an infected animal into a non-contaminated
herd can create herd contamination. Foot rot microorganisms
can also be carried to soil on visitors' boots. Keep visitors
out of pastures or request them to wear disposable or rubber
boots when walking through pastures. This is a biosecurity
measure that can help minimize farm-to-farm transfer of D.
nodosus and F. necrophorum. Reports indicate that direct transmission
of foot rot can occur between cattle, sheep, and goats that
are in/share the same pastures.
Research has shown that genetic makeup helps
determine whether an animal is resistant or susceptible to
these hoof problems. Among sheep, the Merino breed is more
susceptible, and the Gulf Coast breeds are more resistant.
Boer goats are more susceptible, and the Spanish and Kiko
breeds are more resistant to foot rot and foot scald. |
The first signs of hoof rot
or scald are limping, holding limbs above the ground, grazing
on knees, and reluctance to walk. Foot scald is characterized
by interdigital inflammation. The skin between the toes is
pink to white in color, raw, moist, and very sensitive to
the touch. Foot rot can be mild or severe. The erosion of
tissue between the sole of the toe and the hard outer hoof
characterizes foot rot. Upon trimming the hoof, the outer
shell of the hoof will be separated from the inner sole. Severe
cases of foot rot may be accompanied by the presence of pus
and a foul smell. Animals with severe foot rot might show
fever, loss of appetite, with hoof deformity. Animals with
chronic infections show a loss of body condition and decreased
production, resulting in an unhealthy animal overall. Although
foot rot and foot scald are common in small ruminants, they
should also be inspected for other foot diseases or injury. |
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