| border disease without nervous signs or fleece changes. | a natural infection with border disease virus occurred in a flock on low ground in argyll in the spring of 1984. the outbreak was unusual in that the typical clinical signs of border disease, ie, tremor and, or, fleece changes were not present; manifestations of disease were restricted to abortion and the birth of small weak lambs. the disease was shown to have been introduced to the flock by four healthy ewes persistently infected with border disease virus among a group of 39 purchased in octob ... | 1987 | 3576934 |