|
|
|
Restocking is usually permitted after a minimum of 21 days
have elapsed since final cleaning and disinfection. As instances of recrudescence
of disease are well recorded, it is usual to restock in the first instance
with a limited number of susceptible animals.
The following guidelines apply:
• sentinel animals should be tested and shown to be free from antibody to FMD virus at
the start of the exposure period.
• sentinels should be introduced to every building or animal-holding area on the farm.
If this is not possible sentinels should be moved from one building to another and
restocking should not take place until the required time after housing in the last
building.
• sentinels should be observed for clinical signs daily, if possible, for the first 14
days after introduction and then regularly for a further 14 days (i.e., two incubation
periods).
• blood samples should be collected 28 days after introduction or final movement on the
farm and examined for antibody to FMD virus.
• seroconversion from a seronegative to a seropositive status should be taken as evidence
of subclinical infection.
• in the event of clinical disease, or clear evidence of subclinical infection, an
outbreak should be declared. The sentinels should be slaughtered and destroyed and the
entire cleaning, disinfecting and restocking cycle re-started.
• if the sentinels remain clear then phased restocking should be allowed
by introduction of a limited group of animals in the first instance followed
a minimum 14 days (one incubation period) later by full restocking, provided
that clinical and possibly serological examination of animals reveals
no signs of infection.
|
