Foot-and-Mouth is like most diseases in that the severity varies remarkably
from one individual to another and from one farm to another.
In case you have not seen it, there is an excellent new book out which
reviews information about the effects of a wide range of stresses on animals
(pets and horses as well as farm animals).
"Physiology and Behaviour of Animal Suffering"
by Neville G Gregory
I have put a Contents list and Review online at: