Foot and Mouth Disease - Know it well

Foot-and-mouth disease (FMD) is a severe, highly
contagious viral disease of cattle and swine. It also
affects sheep, goats, deer, and other cloven-hooved
ruminants. FMD is not recognized as a zoonotic
disease.

The disease is characterized by fever and blisterlike
lesions followed by erosions on the tongue and
lips, in the mouth, on the teats, and between the
hooves. Most affected animals recover, but the disease
leaves them debilitated. It causes severe losses
in the production of meat and milk.

What Causes It
FMD is caused by a virus. Signs of illness can appear
after an incubation period of 1 to 8 days, but often
develop within 3 days.
The virus survives in lymph nodes and bone marrow
at neutral pH, but is destroyed in muscle when pH
is less than 6.0, i.e., after rigor mortis. The virus can
persist in contaminated fodder and the environment
for up to 1 month, depending on the temperature and
pH conditions.
There are seven known types and more than 60
subtypes of the FMD virus. Immunity to one type does
not protect an animal against other types.

Signs
Vesicles (blisters) followed by erosions in the mouth
or on the feet and the resulting excessive salivation
or lameness are the best known signs of the disease.
Often blisters may not be observed because they
easily rupture, leading to erosions.
These signs may appear in affected animals
during an FMD outbreak:
• Marked rise in body temperature for 2 to 3 days.
• Vesicles that rupture and discharge clear or cloudy
fluid, leaving raw, eroded areas surrounded by
ragged fragments of loose tissue.
• Production of sticky, foamy, stringy saliva.
• Reduced consumption of feed due to painful
tongue and mouth lesions.
• Lameness with reluctance to move.
• Abortions.
• Low milk production (dairy cows).
• Myocarditis (inflammation of the muscular walls
of the heart) and death, especially in newborn
animals.
Animals do not normally regain lost weight for
many months. Recovered cows seldom produce milk
at their former rates, and conception rates may be low.

Thanks
Srini
Sha Dairy Research labs